Department of Chemistry ECONOMY

GENERAL DESCRIPTION Chemistry is the base for development of many topics of natural science such as physics, material science, biology, environmental science and medicine. The interdisiplinary nature of chemistry is reflected in the teaching and research of the department. However, it is of importance to note that the fundamental aspects of chemistry are essential and necessary parts for such an engagement. The research of the department is very extensive and covers a wide range of chemistry. Most of the personnel of the department is engaged in both research and teaching. The research is of fundamental (pure) as well as applied nature. Many of the research projects within the fields of material sciences, environmental sciences, biochemistry, biology, ecology and medicine are of interdisciplinary nature.

(SEK thousands)

Faculty grants for undergraduate teaching

10974

Faculty grants for research and graduate teaching

28530

Project grants from governmental research councils (NFR, TFR, SJFR and FRN)

11762

Project grants from other governmental sources

12509

Grants from private foundations and industry

10014

Grants from foreign sources (EU-projects and industry)

1349

Grants from other sources

1845

TOTAL

76983

The department, with more than 120 scientists, graduate students and technical/administrative staff members, is organized in seven collaborating divisions, which represent scientific competence in the following fundamental topics of chemistry: analytical, inorganic, nuclear, organic, physical, surface and theoretical chemistry. The department also hosts a Nutek competence centre, Surfactants Based on Natural products and three SSF-programs: Nanochemistry, Digital Printing and SELCHEM.

Undergraduate teaching The Chemistry Department gave courses to about one thousand students, corresponding to 186 full time students, which is a 6% decrease since 1999. The examination rate is high, 80% or 148 håp (corresponding fulltime student equivalents). The quality of students, courses and teachers is still very high according to various evaluations even if we have considerable problems with finances and lab space. The new educational programmes K99 and Bio99, launched in 1999, are running this year. The results are promising with respect to examination rate and quality. The chemistry courses in these new programmes have a stronger emphasis on chemical dynamics and molecular chemistry, which are key areas for future development and therefore strengthen the future engineers in their career possibilities. For the new programmes we have more applicants than availble positions both for the chemical civil engineers and for the biotechnological engineers, although only 90% have the chemical engineering programme as the first choice. Our main concern is the laboratory facilities, both to keep the equipment up to date and to afford the laboratory space needed.

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The staff of the department directs, supervises and teaches a majority of the compulsory courses given to MSc students (188 first-year and 142 secondyear) in chemical engineering (“civilingenjör”) during their first three years of study. Besides, we also participate in teaching the students of the BSc students (45) in chemistry (“högskoleingenjör”) and give general chemistry courses for MSc students in other engineering directions. The major compulsory courses given in year 2000 were: (in detail at http://hymer.midgard.kth.se/studiehandbok.asp) Introductory chemistry (year 1, 4 credits) Organic chemistry 1 (year 1, 5 credits) Chemical equilibrium (year 1, 4 credits) Chemical thermodynamics (year 2, 5 credits) Physical chemistry (year 2, 10 credits) Organic chemistry with biochemistry (year 2, 10 credits) Analytical chemistry (year 3, 5 credits) for the MSc students in chemical engineering (note that our old and new K99 curricula partly overlapped for year 2) and General and physical chemistry (year 1, 5 credits) Organic chemistry (year 1, 5 credits) Analytical chemistry 1 (year 1, 5 credits) Statistics (year 1, 3 credits) Analytical chemistry 2 (year 3, 5 credits) for the BSc students in chemistry and General chemistry for students in civil engineering (year 2, 5 credits, 102 students) Physical chemistry for student in industrial economy (year 2, 7 credits, 10 students) for other MSc students. The advanced (optional) courses given by the different divisions within the department are listed under the specific division. We are also involved in extensive continued education for employees of the industry (about 75 students). 33 students made their diploma work at our department and about 210 students followed the postgraduate courses, which cover various aspects of chemical research represented at our department. Staff 11 professors 23 senior teachers 4 technicians 6 secretaries All members of the staff are involved in the various activities such as teaching, research and administration.

Finances The undergraduate teaching has its own budget, based on 26,151 SEK for each produced hås and 25,826 SEK for each produced håp (see above) and an extra support of 1,2 MSEK for the training laboratory.

Trygve Eriksen Professor Head of department

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Analytical Chemistry Analytical Chemistry is of fundamental importance for the entire field of chemistry, since it deals with the development of tools, methods and techniques, for obtaining qualitative and/or quantitative information on the presence of, or interactions between, components in chemical systems. In the search for new measuring principles, Analytical Chemistry employs both fundamental physical or chemical principles, but also more specific principles, from e.g Biochemistry. Analytical chemistry is taught at the undergraduate level for the students in Chemical Engineering, with advanced courses being given in the final year. Johan Roeraade is chair professor.

Research and teaching staff: Johan Roeraade, professor Lars-Göran Danielsson, Ph. D, lecturer (associate professor) Åsa Emmer, Ph. D, assistant professor (associate professor Dec. 2000) Folke Ingman, prof. emeritus Sten Johansson, Ph. D. Adjunct (retired Oct. 2000) Lars Renberg, PhD., Adjoint professor (20%) Catharina Silfwerbrand-Lindh, M. Sc., Adjunct (acting) Peter Lindberg, PhD, researcher (until Nov. 2000)

ADVANCED UNDERGRADUATE COURSES Administrative and technical staff:

Industrial analytical chemistry (5 credits) Organic and Biochemical separation methods (4 credits) Organic and Biochemical separation methods (5 credits) Production and Utilization of Chemical Data for Process Optimization and Control (5 credits)

Rolf Jansson, Laboratory technician Kicki Price, Intendent

Graduate students:

GRADUATE SCHOOL Registered and active graduate students:

17

PRESENTATIONS OF AND INFORMATION ON RESEARCH AND TEACHING ACTIVITIES The Analytical chemistry division is active in informing various groups of the society about its research and teaching acitivities. This is done e.g. by giving short courses to industry and by being active in arranging workshops in cooperation with the Swedish Chemical Society. The transfer of knowledge to industry is mainly performed by running cooperative research projects with several industries, and by arranging workshops and seminars. A PhD course ”Processanalysis and instrumentation” was arranged at the department within the framework of the NORFA network Nordic Institute for Chemometric Education (NICE). The course gave 5 credit points and was attended by 21 students. A Special PhD Course in Nanochemistry was arranged for the students in the SSF programme ”Nanochemistry”. The course is 3 credits, and consists of seminars and lectures by students as well as external experts. Also, a summer school was arranged by the program. For further details, see the webb site of the program www.nanochem.kth.se.

Ola Berntsson Erik Furusjö Anders Hanning (graduated April 2000) Erik Litborn (graduated May 2000) Johan Pettersson Matthew Rice Johan Sjödahl Malin Svedberg Xiaotian Yang Andreas Woldegiorgis Mario Curcio Anders Björk Theres Redeby Fredrik Aldaeus Gustav Sundqvist Thomas Johansson (ABB) Kurt Benkestock ( Pharmacia Upjohn)

RESEARCH The research in Analytical Chemistry at KTH covers a wide range of topics. One is the development of miniaturized analytical, chip-based systems with main applications in organic separations, e.g. DNA fractionation and in protein analysis. Also, fundamental work in separation science, notably in miniaturized electrophoresis, covers an important part of the research efforts. Furthermore, the department is carrying out research in the area of mass spectrometry (MALDI-TOF MS, Electrospray etc), where the main goal is the analysis of biomolecules. Fundamental as well as applied work is done. Another activity is the development of spectroscopic and

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Analytical Chemistry

Premises: Modern research laboratories and offices (500 m 2) in a reconstructed building (1987). Recently reconstructed (1990) laboratories for teaching and experimental training offering modern facilities for analytical, inorganic, organic and physical chemistry (1781 m2).

Equipment: Up to date instrumentation for AAS, GFAAS, ICP, NIR-spectroscopy, Raman Spectroscopy and FTIR-in-situ, as well for GC, HPLC , TLC, Mass Spectrometry (GC-MS), MALDI TOF MS, MS-MS, capillary electrophoresis and electrochromatography, flow injection analysis Special facilities for robotized chip-based nanoscale chemistry and microfluidics. Several CE-instruments with laser induced fluorescence detection for DNA sequencing ( one lane and array instruments), including a high resolution CCD device. Computer facilities and software for chemometrics. as well as facilities for process chromatography and continuous titration.

electrochemical methods in conjunction with chemometrical methods for data evaluation, with application to measurement directly in industrial processes (process analytical chemistry). Research work is also carried out in Process Separation Technology (gas chromatography) where new techniques are developed for on- line analysis. Likewise, projects, focused on the chemical monitoring needs in the pulp and paper industry are ongoing.

SHORT PRESENTATIONS OF THE RESEARCH GROUPS Research leader: Johan Roeraade The research group is active in several areas. Miniaturized analytical systems are developed, where capillary electrophoresis as well as chip based systems are employed . This involves the development of basic technology as well as new separation principles (e.g. nanocapillary electrophoresis), new miniaturized detectors/sensors (optical and optomechanical devices) and new separation media (gel chemistry). The latter is developed for fractionation of DNA fragments, including SNP analysis, which is an extension of two earlier Biomed EU projects, along with the development of new detection principles for array systems. Chip-based chemistry on a nanoscale is developed for protein analysis, identification and sequencing as well as for DNA analysis (including nanoscale PCR). Efforts are also made in the area of miniaturized combinatorial chemistry, where we aim to develop an integrated platform for high throughput synthesis and analysis. Moreover, the group is developing new technology and methodology in capillary gas chromatography, mainly for environmental and process monitoring. Also, the group develops automated on-line analytical sample workup, separation and monitoring systems for the pulp and paper industry .The group has active collaborations/joint projects with several industries and with different disciplines, such as Solid State Physics, Optics, Biochemistry, Molecular Biology, Pulp and Paper Chemistry, etc, both in Sweden and abroad. The group leader is also a member of the NUTEK competence centre in Micro Structure Technology (SUMMIT). A comprehensive program in Nanochemistry, supported by SSF has it´s ”home base” at the department. Johan Roeraade is the program director. The initiative is an interdisciplinary effort to explore fundamental chemical phenomena at a nanoscale level. The duration of the program is 5.5 years. Participating groups at KTH comprise Polymer Chemistry, Organic Chemistry, Surface Chemistry, Analytical Chemistry and Micromachining (Signals, Sensors and Systems). The program has been active since 1999. Research Leader: Lars-Göran Danielsson The area of interest of this group is process analysis. Process analytical research has come into focus only during the last years. The aim of the work is to develop analytical methodology for use in connection with industrial processes in its widest sense. This involves both the development of new techniques and fundamental studies of the application of known techniques to the process environment, in both cases often with the aid of chemometrics. The area is truly interdisciplinary and co-operations with researchers from the technical departments of the Institute as well as with industry and instrument suppliers/manufacturers are essential. Current projects are focused on the paper and pulp industry and on pharmaceutical production. As an example we have developed a method for on-line determination of sulfide and released lignin during kraft cooking. We are also involved in fundamental studies of the application of Near Infrared Spectroscopy (NIR) to pharmaceutical powders and in the development of chemometric

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Analytical Chemistry techniques for the evaluation of spectra from the in-line monitoring of synthesis reactions using mid-IR. We participate in the interdisciplinary program Centre for Chemical Process Design and Control, CPDC, financed by the Strategic Foundation for Research (SSF) where the focus is on interaction between measurement, design and control aspects.

Spectroscopic monitoring of batch reactions and efficient chemometric evaluation of the data obtained L. G. Danielsson, E.Furusjö and A. Björk The overall objective of this project is to develop new tools for measurements on chemical process systems giving access to information relevant for modelling and control. The work involves both new methods for generating data and new chemometric tools for extracting chemical information from these data. The causes for variability in a process will be identified and linked to parameters such as yield and product quality. A final objective is the design of a monitoring system for the processes giving the needed chemical information to the control system. Traditionally chemical process development is based upon chemical information obtained from simplified laboratory systems often with the analyses performed off-line. The relevance of the data so obtained for the actual process is often questionable. With appropriate interfaces many techniques can today be used for in-line or on-line measurements. This often gives a more efficient measurement and the relevance is secured. The development of such measurement systems and of methods for the extraction of chemical information from the data is performed in a sub-discipline of Analytical Chemistry usually referred to as Process Analytical Chemistry (PAC). Recent developments in computer technology and algorithms have made the handling of large multivariate datasets feasible. Even the handling of multivariate models in real time is becoming routine. This makes it possible to monitor one or a few concentrations based on e.g. spectral data. More recently, the use of two- or three-dimensional data for obtaining chemical information has been introduced. Such data can e.g. be used to determine kinetic constants and to choose among mechanisms directly from spectral data without determining the concentrations separately. This development has not come to an end.

RESEARCH PUBLICATIONS AND PARTICIPATION IN SCIENTIFIC MEETINGS Apart from reports to various research councils, 13 scientific papers have been published or are in press in international journals during 2000. Staff members and graduate students of the department have participated in a considerable number of international scientific meetings.

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Inorganic Chemistry Research and teaching staff: Robert Arnek, PhD Julius Glaser, prof. Ingmar Grenthe, prof. emeritus Lars Kloo, prof. Erzsébet Neumann, PhD Ann-Chatrin Nilsson, res. assoc. Ignasi Puigdomenech, PhD Magnus Sandström, prof. Olle Wahlberg, PhD Märtha Åberg, PhD

Inorganic chemistry of today is the chemistry of the elements, and especially of their coordination compounds. Active research is also performed in border areas towards organic chemistry, catalysis, materials, biochemistry and physics.

Bio-coordination Chemistry Medical technique

Administrative staff: Kenneth Andersson, intendent Ewa Nyström, secretary Irena Desselberger, technician Anders Eriksson, technician Folke Fredlund, laboratory technician Ernst Hansen, instrument technician Jan Johansson, network technician

Coordination Chemistry

Materials Chemistry Materials Science

Organometallic Chemistry Catalysis

The research in inorganic chemistry at KTH has its basis in our competence in coordination chemistry in solution and in solids. A broad spectrum of scientific problems in chemistry and related fields are studied: from the coordination of metal ions to metal-organic compounds, clusters of metal ions, inorganic polymers and bio-inorganic model systems. The activities comprise development of synthetic routes for preparation of coordination compounds and the characterisation of their spectroscopic, structural, dynamic and other physicochemical properties. Relations are studied between structure and chemical properties, e.g. reactivity, catalytic and biochemical activity, by means of a large number of experimental techniques and theoretical calculations. Both fundamental research and application-oriented projects are pursued.

UNDERGRADUATE TEACHING The teaching programme includes courses in inorganic, bio-inorganic, materials and general chemistry, given for students of chemistry and of other faculties of KTH. Moreover, advanced courses are given for the final year chemistry students, as well as specific topics given for post-graduates and for continued education of industrial employees. A special consideration is given to the use of chemistry-related databases and computerised information retrieval. Here, crystal structure databases, powder diffraction computer files as well as thermodynamic databases are used in freshmen students’ courses. New advanced courses in Bio-inorganic Chemistry and in Materials Chemistry have been developed during this year.

DIPLOMA WORK Three students have done their diploma work at this Department studying i.) coordination chemistry of platinum and thallium compounds in solution and ii.) cluster chemistry in solution

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Inorganic Chemistry RESEARCH ACTIVITIES ELECTRON TRANSFER PROCESSES IN LIGHT-HARVESTING OLIGOMETALLICS

Visiting scientists and graduate students:

Project leader: Julius Glaser Participating scientists: István Bányai, Hungary; Tina Dolidze, Georgia; Lars Ericsson, Stockholm University; Dimitri Khoshtariya, Georgia; Mikael Kritikos, Stockholm University; Imre Tóth, Hungary; Göran Lindbergh, Electrochemistry Dept., KTH PhD students: Andrea Bodor, Gui-bin Ma, Mikhail Maliarik Diploma students (EU Erasmus programme): Peter Nagy

Anette Bergelin Wenche Aas, Norway István Bányai, Hungary Andrea Bodor, Hungary Tina Dolidze, Georgia Ildiko Farkas, Hungary Elena Gueorguievskaya, Russia Farideh Jalilehvand, Iran Dimitri Khoshtariya, Georgia Patric Lindqvist-Reis Gui-bin Ma, China Mikhail Maliarik, Russia János Mink, Hungary Mikhail Skripkin, Russia Imre Tóth, Hungary Zoltan Szabo, Hungary

The project aims at deeper understanding of some fundamental processes in inorganic solution chemistry: speciation, structure and mechanisms of ligand exchange, complex formation and electron transfer reactions, both for normal reactions and those in chemical equilibrium. Electron transfer study between metal ions is facilitated if long-lived intermediate forms where the metals are bonded to each other. In such a case, experimental studies of the intermediate become possible and Marcus theory treatment is simplified due to low number of uncertain parameters. To this end, we have synthesised a new family of long-lived metal-metal bonded complexes: both metals have two possible oxidation states differing by two electrons. Thus, 2-electron transfer can be studied in depth which opens new perspectives for a better insight into this important process. Structure of the metal-metal bonded compounds in solution and in solid state In our search for oligometallic compounds aimed to improve absorption and electrochemical characteristics of the light-harvesting process in the ‘wet’ solar cell we have modified the previously described Pt-Tl complexes (Inorg. Chem. 37 (1998) 2910, and J. Am. Chem. Soc. 117 (1995) 7550) by varying the ligands in the coordination sphere of the coupled metal atoms. The oligonuclear Pt-Tl cyano compounds exhibit an ability for photoinduced two-electron charge transfer processes. Absorption of light quanta initiates a redox reaction between the bound platinum and thallium atoms. This is a rare case of a metal-to-metal charge transfer via a direct polar metal-metal bond. In dark and at room temperature the complexes are stable in solution whereas both lightinduced and thermal pathways bring about transfer of two electrons between the coupled metals. Both the rates and the products of redox decom2.00 position of the binuclear [(NC) 5Pt-Tl(CN)n]n(n=0-3) species are dependent on the original Pt-Tl 1.15 2.50 complex. The kinetic inertness increases with the 1.98 2.30 increase of the number of CN- groups in the com1.15 pounds. The only product of thallium reduction in the binuclear Pt-Tl species is Tl+, while oxidation of platinum leads to different complexes of Pt(IV). Depending on the starting compound either [Pt(CN) 6] 2- or the hitherto unknown species [Pt(CN)5(OH)]2-, [Pt(CN)5H2O]- are formed in solution; the former two complexes have been prepared in solid state as well, with a monovalent Pt Tl thallium as a balancing cation. Hence, a net complimentary two-electron transfer reaction proceeding via formation of the binuclear [(NC)5Pt-

Structure of the solid compound TlPt(CN)5, upper: two unit cells showing the linear -N2C2-Pt-Tl-N2-C2-Pt- chains along the c-axis (distances in Å); lower: Structure fragment showing a Pt-Tl unit surrounded by four antiparallel units connected by bridging cyano (C1-N1) ligands.

Tl

Pt

Tl N1 C1

Tl 2.628

N2 C2

Pt

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Inorganic Chemistry Tl(CN)n]n- intermediates take place: PtII + TlIII ⇐⇒ Pt-Tl ⇐⇒ PtIV + TlI II 2Pt + TlIII ⇐⇒ Pt-Tl-Pt ⇐⇒ [PtIII]2 + TlI

1.15

Pt and Tl L III edge EXAFS studies of the [(NC)5Pt-Tl(CN)n]n- complexes in aqueous solution show short Pt-Tl bond distances: 2.598(4), 2.618(5), and 2.638(5) Å, for n = 1, 2 and 3, respectively. NMR 195Pt and 205Tl chemical shifts, revealing metal-metal charge transfer, confirm that these species are metastable intermediates in a two-electron transfer reaction from platinum(II) to thallium(III). Force constants from vibrational spectra analyzed by normal coordinate methods are used to discuss the delocalized bonding. It has been found that the platinum pentacyano unit of the [(NC)5Pt-Tl(CN)n]n- species is inert towards the tested ligands, whereas the thallium “part” of the complexes can be tuned significantly. We have detected the formation of binuclear Pt-Tl pentacyano complexes with several ligands coordinated to the thallium site: halide ions (F, Cl, Br, I); pseudohalide ions (SCN); and molecular ligands (en, bipy, phen, tetraphenylporphyrine).

N C

N

2.20

C 2.01

2.638

Pt

1.15

Tl

Dynamics of cyanide exchange between Tl(13CN)4¯ and 13CN¯ was studied by means 205Tl and 13C NMR. The rate law consists of two parts: w = kCN [ Tl(CN)4¯][CN¯] + kOH [ Tl(CN)4¯][CN¯] [OH-] with kCN = 9.7(+0.4) x106 M-1s-1 and kOH = 5.4(+0.4) x1010 M-2s-1. It was shown that the exchange between the two cyano species can be studied not only by 13C NMR, but also by 205Tl NMR using the heteronuclear carbonthallium scalar coupling as an indicator, despite the fact that only one Tl site is present in the system. The reaction mechanism is discussed in terms of an associative interchange mechanism, IA. Penetration of the incoming cyanide into the coordination sphere of Tl(CN)4¯ and Tl(CN)4(OH)¯ is suggested to be the rate-determining step for the two parallel (ppm) reactions paths. The possible reasons for the strong labilizing effect of the cyanide ligand is discussed in the light of the ther2980 modynamic and structural data. 3000

3020

3040 (ppm)

3020

3000

2980

Funding

NFR, Trygger Foundation, European Commission, Wennergren Center Foundation. The possibility of detection of an exceptional exchange reaction, namely cyanide exchange between two Tl(CN)4¯ entities by a direct encounter was theoretically settled but found to be too slow for detection.

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Inorganic Chemistry ACTINIDE CHEMISTRY IN AQUEOUS SOLUTION I. Grenthe, I. Farkas, H. Moll and Z. Szabó

I. SOLUTION COORDINATION CHEMISTRY OF URANIUM IN BINARY AND TERNARY SYSTEMS POTENTIOMETRIC AND MULTINUCLEAR NMR STUDY OF THE BINARY AND TERNARY URANIUM(VI)-α-HYDROXYCARBOXYLATE/ GLYCINE-FLUORIDE SYSTEMS

Z. Szabó and I. Grenthe Equilibria, structures and ligand exchange dynamics in binary and ternary U(VI) – L – F-, systems, where L is glycolate, a-hydroxyisobutyrate, or glycine, have been investigated in 1.0 M NaClO4 by potentiometry and 1H, 17 O and 19F NMR spectroscopy. L may be bonded in two different ways, either through the carboxylate end, or by forming a chelate. In the glycolate system the chelate is formed by proton dissociation from the (-hydroxy group already around pH 3, indicating a dramatic increase, at least a factor of 1013, of its dissociation constant on co-ordination to uranium(VI). The L exchange in carboxylate co-ordinated UO2LF32- follows an Eigen-Wilkins mechanism, as previously found for acetate. The water exchange rate, kaq= 4.2 % 105 s-1, is in excellent agreement with the value determined earlier for UO22+(aq). The ligand exchange dynamics of UO2(O-CH2-COO)2F3- and the activation parameters for the fluoride exchange in D2O (k(obs) = 12 s-1, ∆H ≠ = 45.8 + 2.2 kJ mol-1 and ∆S ≠ = -55.8 + 3.6 J K-1mol-1) are very similar to those in the corresponding oxalate complex, with two parallel pathways, one for fluoride and one for the α-oxocarboxylate. The same is true for the L-exchange in UO2(O-CH2-COO)22- and in UO2(oxalate)22-. The exchange of α-oxocarboxylate takes place by a proton assisted chelate ring opening followed by dissociation. As we cannot decide if there also is a parallel H+ independent pathway, only an upper limit for the rate constant, k1< 1.2 s-1, can be given. This value is smaller than those in previously studied ternary systems. Equilibria and dynamics in the ternary uranium(VI)-glycine-fluoride system, investigated by 19F NMR spectroscopy indicate the formation of one major ternary complex, UO2LF32- and one binary complex UO2L2, (L: H2N-CH2COO-) with chelate bonded glycine, and logβ(9) = 13.80 + 0.05 for the equilibrium: UO22+ + H 2N-CH 2COO- + 3 F - = UO2(H2NCH2COO)F32-, and logβ(11) = 13.0 + 0.05, for the reaction: UO22+ + 2H2N-CH2COO- = UO2(H2N-CH2COO)2. The glycinate exchange consists of a ring opening followed by proton-assisted steps (scheme below). The rate of ring opening, 139 + 9 s-1, is independent both of the concentration of H+, and the solvent, H2O or D2O.

F F

O

O

M

F*

O M

F*

k1

O

M

F

F

O

k2 (slow)

F

H2N

F

M (aq)

O

+ H2N

F

+H+ K F

O F

NH2

O

k-1

NH2 F -F- k4 +*FF*

F

O M +

F

H3N

O

F k3

O F

M (aq) F

+

O

+

H3N

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Inorganic Chemistry RATES AND MECHANISM OF FLUORIDE AND WATER EXCHANGE IN UO 2 F 5 3- AND UO2F4(H2O)2- STUDIED BY NMR AND WAVE FUNCTION BASED METHODS.

V. Vallet, U. Wahlgren, B. Schimmelpfennig, Z Szabó, I. Grenthe The rate constant for the exchange between free and coordinated fluoride has been investigated by 19F NMR at -5 oC . The rate of exchange depends only on [UO2F53-], this fact and a rate of reaction that is independent of the concentration of the product UO2F4(H2O)2- indicates a dissociative mechanism with the formation of UO2F42-, with a square bipyramid geometry, as an intermediate. From the integrals of the different individual peaks in new NMR spectra, we obtained the equilibrium constant K5 = 0.60 ± 0.05 M-1 for the reaction (1) UO2F4(H2O)2- (aq) + F-(aq) ⇐⇒ UO2F53-(aq) This value is much smaller than that previously determined, K5= 3.0 M-1. The new value of K5 is approximately the same as that for the formation of UO2(OH)53-. The complex UO2F53- gives one broad 19F-signal with a line-width that is independent of the concentration of UO2F42- and free fluoride. The rate constant for the exchange reaction (eq 2) is equal to k1= (7.0 ± 0.5) x103 s-1. This shows conclusively that the exchange does not take place in an associative mechanism involving free fluoride. It also excludes solvent participation in an interchange mechanism because UO2F4(H2O)2- is not a reactant in the exchange reaction. The reaction mechanism and the transition states have been investigated theoretically using quantum chemical calculations. These studies have been made both using a gas-phase model and by describing the solvent part as conductor like polarised medium (CPCM). Solvent effects turn out to be important both for the geometry and the activation energy of the transition state. Two transition states were identified one, {UO2F42-...F-}≠, for the exchange of fluoride in UO2F53-, the other, {UO2F42-...H2O}≠ for the exchange of water in UO2F4(H2O)2-. The leaving ligand is in both cases located at 3.7 Å from uranium while the position of the spectator ligands have changed only marginally. This is a very strong indication of dissociative activation in both cases. The value of the activation energy is compatible with experimental information. SOLVENT EFFECTS ON URANIUM(VI) FLUORIDE AND HYDROXIDE COMPLEXES STUDIED BY EXAFS AND QUANTUM CHEMISTRY

V. Vallet, U. Wahlgren, B. Schimmelpfennig, H. Moll, Z Szabó, I. Grenthe The structures of the complexes UO2Fn(H2O)5-n2-n, n = 3-5 have been studied by EXAFS. All have pentagonal bipyramid geometry with U – F of and U – H2O distances equal to 2.26 and 2.48 Å, respectively. On the other hand the complex UO2(OH)42- has a square bipyramid geometry both in the solid state and in solution. The structures of hydroxide and fluoride complexes have also been investigated with wave function based and DFT methods in order to explore the possible reasons for the observed structural differences. These studies include models that describe the solvent by using a discrete second coordination sphere, a model with a spherical, or shape adapted cavity in a conductor like polarisable continuum medium (CPCM), or a combination of the two. Solvent effects were shown to give the main contribution to the observed structure variations between the uranium(VI) tetrahydroxide and the tetrafluoride complexes. Without a solvent model both UO2(OH)4(H2O)2- and UO2F4(H2O)2- have the same square bipyramid geometry, with the water molecule located at a distance of more than 4 Å from uranium and with a charge distribution that is very near identical in the two complexes. Of the models tested, only the CPCM ones are able to describe the experimentally observed square and pentagonal Page 10

Inorganic Chemistry bipyramid geometry in the tetrahydroxide and tetrafluoride complexes. The geometry and the relative energy of different isomers of UO2F3(H2O)2- are very similar, indicating that both isomers are present in comparable amounts in solution. All calculated bond distances are in good agreement with the experimental observations, provided that a proper model of the solvent is used.

A

B

C

Uranium(VI) trifluoride isomers; structures A and C in gas-phase using C2v symmetry and structure B in the solvent without symmetry constraints. The uranium and the hydrogen atoms are black; the fluoride atoms light gray and the oxygen atoms medium gray. Thin lines denote the distance between non-bonded atoms and the dashed lines hydrogen-bond distances. Distances in Å.

THE MECHANISM FOR WATER EXCHANGE IN [UO2(H2O)5]2+, AND [UO2(oxalate)2(H2O)]2AS STUDIED BY QUANTUM CHEMICAL METHODS.

Valérie Vallet, Ulf Wahlgren, Bernd Schimmelpfennig, and Ingmar Grenthe The dissociative (D), associative (A) and interchange (I) mechanisms for the exchange of water between [UO2(H2O)5]2+, [UO2(oxalate)2(H2O)]2- and water solvent has been investigated using quantum chemical methods. The choice of exchange mechanism is based on the computed activation energy and the geometry of the identified transition states and intermediates. These quantities were calculated using the HF geometry and the MP2 energy, both in gas-phase and using a conductor-like polarizable continuum model (CPCM) for the solvent. There is a significant difference between the activation energy in the two models, the energy barrier for the D mechanism increases in the solvent as compared to the gas-phase, while it decreases for the A and I mechanisms. The activation energy ∆U≠ for the D, A and I mechanisms in the CPCM model are 6x.y, 18.7 and 15.8 kJ/mol, respectively. The small energy barrier between the intermediates and the transition states in the D and A mechanisms indicates a life-time ≈10-10 s-1 for the intermediate; the energy and the structure of the intermediate in the A mechanism are very near the same as those in the I transition state. This makes it impossible to distinguish between the two mechanisms experimentally and most likely also using theory. The theory based activation energy for the A/I mechanism, ≈18 kJ/mol is in fair agreement with the experimental activation energy, 26 + 1 kJ/mol, indicating that the D mechanism for water exchange in UO2(aq)2+ can be ruled out. It should be feasible to get an experimental confirmation of this by determining the activation volume, the theory based values of ∆V≠ for the D and A/I mechanisms are 4.y and 3.4 cm3/mol, respectively. The water exchange in the complex [UO2(oxalate)2(H2O)]2- containing two more rigid bidentate oxalate groups Page 11

Inorganic Chemistry seems to follow a different water exchange mechanism, as indicated by theory based results from the gas-phase model (the CPCM model could not be studied due to the very time consuming calculations). The activation energy for the D mechanism is now lower than those of the A/I mechanisms. The activation barrier between the D-transition state and the four-coordinated intermediate is large approx. 35 kJ/ mol, indicating a life-time of 10-5 s-1, sufficiently long to influence the kinetics of ligand exchange reactions as suggested in some of our previous studies.

Perspective view of the transition state {[UO2(H2O)5...(H2O)]2+}≠ formed in the A mechanism in the solvent. The uranium atom and the hydrogen atoms are black and the oxygen atom medium grey. Distances are in Å.

ON THE STRUCTURE OF Np(VI) and Np(VII) SPECIES IN ALKALINE SOLUTION STUDIED BY EXAFS AND QUANTUM CHEMICAL METHODS

Hélène Bolvin, U. Wahlgren, Henry Moll, Tobias Reich, Gerhard Geipel, Thomas Fanghänel and Ingmar Grenthe The bond distances and co-ordination numbers of the predominant Np(VII) complex in strongly alkaline solution have been determined using EXAFS transmission measurements. The stoichiometry and structure of NpO4(OH)23- has been deduced by combining these data with different structure models, mostly determined by using DFT based methods. The experimental and theory based distance Np(VII) - Ooxo is 1.894 and 1.90 Å, respectively, while the Np(VII) – OH- distance is 2.326 and 2.33 Å, respectively. Theory based geometry and bond distances have been obtained also for other Np(VII) and Np(VI) complexes, NpO 2 (OH) 4- , NpO 4 - , NpO4(OH)24- and NpO2(OH)42-, NpO42-. The “NpO6” – unit has a square bipyramid geometry both in NpO4(OH)23- / 4- and in NpO2(OH)41- / 2-, albeit with some difference in bond distances. The close similarity in structure indicates that no major rearrangements are necessary on electron transfer between Np(VI) and Np(VII), a possible explanation for the stable and reproducible Np(VII)/Np(VI) redox potential observed in alkaline solution. The structure data indicate that new Np(VII) species may be identified by oxidation of Np(VI) solutions at lower hydroxide concentrations. Funding

European Union TMR program, contract ERBFMBIC post-doctoral position, Franz Georg and Gull Liljenroth´s Stiftelse, European Community for Concerted Action JETDEM, The Carl Trygger foundation for Scientific Research, European Community, “ACTAF” program European Community, beamtime and travel expenses for work at the European Synchrotrone light source (ESRF) in Grenoble. Income from consulting

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Inorganic Chemistry The Synthesis, Structure and Chemical Bonding in Cluster and Lowdimensional Compounds Project leader Lars Kloo Graduate Students: Martin Lindsjö, Helene Paulsson, Jan Rosdahl The research of the group is mainly devoted to the study of discrete and extended inorganic clusters; the conditions of formation and the relationship between structure, bonding and physical properties. Clusters are essential model systems for the understanding of the relationship between microscopic and macroscopic properties of theoretically and technologically important compounds. Clusters are often found as fundamental structural units in compounds with special physical properties, such as super- or semiconductors. However, traditional cluster chemistry is very much focused on clusters isolated in the solid state, but remarkably little (or nothing) is known about clusters present in the reaction media used; such information is vital for the understanding of the thermodynamic and/or kinetic conditions of cluster formation and stability. Three known bismuth clusters; Bi53+, Bi82+ and Bi95+.

The philosophy/strategy of our cluster research is to develop a library of easy-to-use reaction media at room temperature, whose properties can be characterised in detail using a multitude of experimental and theoretical methods. The next step is to use these reaction media to synthesise cluster and lowdimensional compounds. In this context special attention is paid to the correlation between the solution cluster composition and the solid compounds formed, as well as the similarities and differences in bonding properties of discrete and extended cluster frameworks. Recently, also matrices, such as inorganic clathrates, zeolites and aromatic polymers, for the stabilisation of clusters and unusual oxidation states have been explored. It is my hope and belief that this approach will provide a significant insight into the chemistry of clusters and related systems. The effort has over the last years mainly been focused on the synthetic aspects and the proper understanding of the chemistry in the reaction media in terms of the coordination chemistry and bonding properties. We have also started to apply this knowledge to grow crystals with designed structural fragments; in particular, low-dimensional compounds of condensed clusters have been of interest to us. Although our research is fundamentally curiosity-driven, the step to applications of potential interest to industry is small. The research involves both cationic and anionic clusters, extended clusters and low-dimensional compounds with anisotropic electrical properties (one-dimensional metals and semiconductors); the development of reaction media for controlled synthesis, structural and spectroscopic characterisation and evaluation of physical properties. During the year 2000 also studies of hybrid inorganic/organic materials have been initiated aimed at multifunctional magnetic materials.

The step from discrete Bi95+ clusters in Bi6Cl7 to extended chains in Bi4Br4 and Bi14I4 is small.

The polymeric structure of the extremely iodine-rich compound (Me3S)3I26.

Funding

NFR (Swedish Natural Science Research Council), TFR (Swedish Research Council for Engineering Sciences), SSF (Foundation for Strategic Research), INTAS, KTH.

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Inorganic Chemistry The Interaction between Cations and Biological Macromolecules: Appplied Bio-coordination and Medicinal Chemistry Project leader Lars Kloo Graduate Students: To be recruited Visiting Scientists: Dr. José Mánuel Matínez, Univ. of Sevilla, Spain Biotechnology and medical technology are two vividly expanding research areas today. However, the focus is on the biological molecular systems. A large number of the naturally existing enzymes are so-called metalloenzymes, thus containing metal ions as essential components for the biological function. It is my opinion that the role of the metal ions in enzymes and also in regulatory mechanisms involving nucleotides is a neglected area and also one where the coordination chemistry strategy, describing the system from the viewpoint of the metal coordination centre with the help of a multitude of experimental techniques and theoretical methods, can provide important insights into the structure, mechanisms and properties of a large number of macromolecular biological entities. New projects have been initiated in this area concerning the cation effects in tar-HIV and prion proteins. The new projects both involve applied ones focusing on the problems of atherosclerotic plaques (in co-operation with Gambro Lundia AB and Lund Univ.) and the development of bio-compatible materials (in co-operation with the Glass Research Institute and Stockholm Univ.), as well as more fundamental ones concerning the interaction between “trivial” cations (e.g. Li+, Mg2+, Ca2+ etc.) and polypeptides and polynucleotides; the effects on conformation and dynamics. The instantaneous conformation of an octanucleotide in the presence of explicit water.

Funding

Svenska Institutet, Gambro Lundia AB, MCFI, KTH.

Coordination, Bonding and Electron Structure in Solvated Metal Ions and Complexes, Experimental and Theoretical Studies Project leader Magnus Sandström Post Docs and Graduate Students: Farideh Jalilehvand, Patric Lindquist-Reis, Elena Gueorgievskaia Visiting Scientists János Mink, Hungary; Mikhail Skripkin, Russia; Alireza Molla-Abbasi, Iran. Research Objectives The structure and bonding of metal ions and complexes are studied in order to understand their chemical properties. Characteristic for this project is the broad range of experimental techniques employed, aided by theoretical calculations, which enables deep probing of the chemical problems, which are chosen within a wide range. Special attention has been devoted to the solvation and coordination chemistry of metal ions with distinguishing coordination features (e.g. due to ligand field, Jahn-Teller and covalency effects (e.g. Hg, Cu, Ag, Au) and of environmental interest (e.g. U, Hf, Zr, Rh, Ir, Pt, Tl, Hg, Ca).

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Inorganic Chemistry Results Solvation of metal ions. Synchrotronbased EXAFS spectroscopy, X-ray Large Angle Scattering (LAXS), and crystal structure investigations have been used to study the structure and hydrogen bonding around hydrated trivalent ions in aqueous solution, e.g. for the d0 ions Sc3+, Y3+, La3+ and their d10 counterparts Ga3+, In3+. Combined EXAFS and Molecular Dynamics studies have been made of the hydration of the biochemically important Ca2+ ion.

The hydrated calcium(II) ion

Weak hydrogen bonding in the crystal structure of N,N-dimethylformamide

The results show that in aqueous solution 8 water molecules surround the calcium(II) ion in an asymmetric distribution with a mean Ca-O distance of 2.46 Å. The hydration of the U4+ ion, of interest for nuclear waste storage problems, has also been studied. Other solvents of widely differing coordinating properties (e.g. methanol, dimethylsulfoxide, dimethylpropylene urea, acetonitrile, pyridine, N,N-dimethylformamide (dmf ), N,Ndimethylthioformamide (dmtf ), liquid ammonia) are used to bring out special coordinating properties, in particular for heavy metal ions such as Hg2+. Low temperature crystal structures have been made of the solvents dmf and dmtf in order to study the weak intermolecular interactions. A number of cyanide complexes of Pt, Tl, Hg, Au, including bimetallic Pt-Tl and Pt-Pt complexes, have been studied with EXAFS and vibrational spectroscopic methods to characterize the bonding and coordination around the metal atoms. • Crystal structures of new rhodium(III), yttrium(III) and thallium(III)dimethylsulfoxide complexes have been solved. • The influence on bonding and coordination of transition and p-block element complexes by so-called Jahn-Teller effects is being investigated. The first-order Jahn-Teller effects in some hexa-coordinated Cu(II) solvates, which in crystal structures appeared to have a regular coordination, are shown by EXAFS methods to have 4+2 coordination. Secondorder Jahn-Teller effects due to near-degeneracy of electronic states of appropriate symmetry, are prominent in Hg(II), Au(I), Cu(I) compounds, but also of importance for Ag(I), Tl(III), Zn(II). In order to enhance such “covalency effects”, strongly coordinating ligands are needed. A number of crystal structure, LAXS and EXAFS studies of coordination complexes with oxygen, nitrogen and sulfur donor ligands, have been performed. Funding:

NFR, Swedish Institute VISBY programme, Wenner-Gren Center Foundation

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Inorganic Chemistry Properties of Humic Substances in Inland Waters Project leader: O. Wahlberg, Graduate student: A. Bergelin Humic material is studied to better understand the transport, storage and availability of nutrients and poisons in natural waters. We have investigated humic material from a brown water lake, Snuggan and also from podzolic soils . It was found that in certain cases solid particles predominate and otherwise a colloidal phase is the main form. Supersaturation often occurs. The acid base properties of the solid phase is very different from that of the colloids. The different forms of the humic material as a function of DOC, pH and salinity has been studied. The results have implications for the transport and storage of metal ions and small organic molecules in natural waters. Properties of Humic Material in Water

Consumption of molecular oxygen in granitic environments Project leader: Ignasi Puigdomenech Consumption of O2 in underground granitic environments: The aim of this project (called REX) was to determine how O2 trapped in a closed nuclear waste repository would react with rock minerals in water conducting fractures in granitic rock. The focus of the project was on an underground experiment conducted at 340 m depth in the Äspö Hard Rock Laboratory (Oskarshamn, Sweden). Because of uncertainties in hydraulic parameters, this field experiment consisted of injection and monitoring of O2 into a borehole reaching an isolated fracture surface. This concept excluded the complications and costs associated with hydraulic multi-hole experiments. The project was performed as an international co-operation, and it consisted of the following parts: a) microbial O2 consumption studied at several sites in the Äspö tunnel (by Göteborgs universitet); b) the in-situ field experiment at Äspö (by KTH); c) the Replica experiment: a laboratory study using the other half of the fracture surface used for the in-situ experiment (by CEA Cadarache, France); and d) laboratory investigations to support the interpretation of the in-situ and replica experiments (by BGS and Sheffield Univ., UK). The results from the in-situ experiment in Sweden were confirmed by the replica investigation performed in France. Both were concordant in showing time scales for O2 uptake in the order of days. The agreement was remarkable when taking into account the differences in experimental conditions. For example, different microbial processes took place in the two experiments. The laboratory studies with rock samples from Äspö demonstrated that microbial activity induced increased chemical weathering, with the formation of clay minerals. Rates of O2 uptake by fracture filling minerals were determined under laboratory conditions. These rates were faster than those reported in literature studies of pure mineral systems, and supported the fast O2 uptake rates obtained in the field and replica experiments. Oxidation of methane by underground microbes was demonstrated, indicating that a substantial reducing capacity should be assigned to CH4 and H2, which diffuse from deep geological sources. Several publications are being written that deal with the different parts of the project.

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Nuclear Chemistry Nuclear chemistry is a fundamental subject comprising isotope chemistry, radiochemistry, nuclear reaction chemistry and radiation chemistry. It has important applications in the fields of isotope engineering, nuclear energy, disposal of radioactive wastes, radiation protection and industrial radiation chemistry. Our research activities are focused on radiation chemistry and radiochemistry. Radiation chemical techniques, e.g. γ- and pulse radiolysis, are most valuable in mechanistic studies on radical reactions, mainly in aqueous media. This fact has initiated a large number of investigations, generally in co-operation with chemists from various fields. The radiochemical research is oriented towards analytical methods in which nuclear properties are involved. Transport of radionuclides in geomedia is an important matter of study.

Research and teaching staff: Trygve E. Eriksen, professor Torbjörn Westermark, professor emeritus Johan Lind, Ph.D. (associate professor) Gabor Merényi, Ph.D. (associate professor) Torbjörn Reitberger, Ph.D. (associate professor) Mats Jonsson, Ph.D. (associate professor)

Technical and adm. staff: Ewa Nyström Kenneth Andersson Kjell Svärdström Birgitta Carell Olle Engman Kristina Ljungqvist

ADVANCED UNDERGRADUATE TEACHING The aim of the undergraduate studies in nuclear chemistry is to provide knowledge and experience which is useful in the nuclear industry, knowledge of the effects of ionizing radiation on dead and living matter etc and to make the students familiar with the analytical methods based on isotope and radiation measurements. The following courses are given annually:

Graduate students: Magnus Carlsson Mats Jansson Erik Johansson Mireia Molera David Stenman Susanna Wold

Nuclear chemistry (5 credits) The nuclear fuel cycle (4 credits) Radical chemistry (5 credits) Nuclear Fuel.Physical and Chemical Properties (5 credits) (new course) GRADUATE SCHOOL Registrated graduate students: 6 DISSERTATIONS 1 Ph. D. and 1 Tekn. lic. 4 Diploma work GRADUATE COURSES Advanced courses in radiochemistry, radiation chemistry, applied radiation chemistry and radical chemistry are given in English on a regular basis

RESEARCH ACTIVITIES RADIONUCLIDE CHEMISTRY Trygve E Eriksen,, Mats Jansson, Mireia Molera, Susanna Wold In an ongoing long term research program we are concerned with chemical aspects on mechanisms for release and migration of radionuclides from a repository for spent reactor fuel. Laboratory experiments and modelling deal with the behaviour of radionuclides in natural systems and the effects of redoxpotential, radiolysis, sorption , complex and colloid formation on the transport of radionuclides in geological systems.

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Nuclear Chemistry COLLOID MIGRATION IN COMPACTED BENTONITE

Premises: Modern research laboratories and offices (480 m 2). Detection systems for various types of ionizing radiation, 60Co-radiation source for γ-radiolysis, pulse radiolysis equipment for kinetic studies of radiation induced chemical reactions. The equipment for pulse radiolysis is the only of its kind in Sweden and it is located in the Alfvén Laboratory.

Trygve Eriksen, Susanna Wold Colloids have been suggested to be potential carriers of radionuclides in diffusive transport through the compacted bentonite clay to be used as backfill in repositories for radioactive wastes and also in flowing water in fractures in the surrounding rock. To quantify the effect of colloids on the migration of radionuclides in geological systems is therefore important in the safety analysis. Humic acids , found at varying concentrations, in natural water may form complexes with cationic radionuclides and thereby change their sorption and migration properties. The effect of humic acid on the speciation and diffusion of radionuclides through clay barriers is studied in laboratory experiments.

IN SITU STUDIES Trygve E. Eriksen, Mats Jansson CHEMLAB is a 15 meter long borehole probe with a diameter of 89 mm, which is used in in-situ experiments in the Äspö-tunnel situated close to Oskarshamn. The aim of the studies is to verify that experimental data from laboratory experiments can be used to predict the behaviour of radionuclides in natural systems. The unique probe is owned by Swedish Nuclear Fuel and Waste Management Co (SKB) and the experiments are performed by Nuclear Chemistry at Royal Institute of Technology. CHEMLAB is constructed by Métro Mesures in Paris. Experiments with radionuclides were started at the end of February 1997 and will continue for at least five to six years. The experiments are descriped in “Programme for CHEMLAB Experiments”. Diffusion of Sr2+, Cs+, Co2+ , I and TcO4- in compacted clay (bentonite) was studied. The results obtained are in exellent agreement with our earlier results from laboratory experiments. A second generation CHEMLAB probe is designed for experiments with actinides and irradiated nuclear fuel . This simplified sond (figure) is presently used for studies of actinide migration in fissured rock. These experiments are carried out in cooperation with a research group at Institut für Nukleare Entsorgung (INE), Forschungszentrum Karlsruhe

RADIATION CHEMISTRY RESEARCH IN RADIATION CHEMISTRY REACTIVE OXYGEN SPECIES Gábor Merényi and Johan Lind During the last years we have been investigating the properties of reactive oxygen species such as peroxyl radicals, ozone, oxyl radicals and peroxides. Alkyl peroxyl radicals in aqueous solutions were found to react with ozone with rate constants between 104 and 105 M-1,s-1. Although previously surmised, this is the first time that these rates have actually been measured. The nonnegligible rates suggest that alkyl peroxyl radicals have to be considered when modelling ozone destruction rates in moist air or during ozone bleaching of e.g: pulp. We have for the first time produced and investigated bona fide aromatic hydroperoxides. These species, which according to textbooks cannot exist, have a fully measurable lifetime, on the order of hundreds of milliseconds. Their lifetime decreases with electron-releasing substituents on the aromatic ring. Quantum-chemical calculations reveal homolysis of the peroxidic O-O bond initially to yield a geminate pair of phenoxyl and hydroxyl radicals as the only reasonable mechanism of decomposition. Surprisingly though, almost no free radicals appear to escape before the pair collapses into catechols. This is rationalized by a very large cross-section for Page 18

Nuclear Chemistry collapse, resulting in the stereoelectronically favoured ortho-carbon-oxygen coupling. After having unravelled the thermochemistry of the biologically important peroxynitrite, we succeeded in demonstrating that the nitration by peroxynitrite of aromatic residues e.g., thyrosine, in proteins, proceeds via a radical mechanism, involving phenoxyl and NO2 radicals. This finding points to possible strategies to protect biological systems, by e.g., employing benign antioxidants. A rather sensational report to the effect that peroxynitrite decomposes to yield substantial amounts of singlet oxygen and nitroxyl (NO-) could also be discarded by us as absurd. We are in the process of elucidating the mechanism of peroxynitrite reactivity towards carbonyl groups. Here we have shown that initial addition to the carbonyl-group is followed by homolysis to yield alkoxyl radicals and NO2. Our findings enable us to determine the thermochemical and redox properties of the alkoxyl radicals thus formed. It should be noted that, normally, alkoxyl radicals rapidly decompose and have thus eluded so far such characterization. Our finding points to the possibility of utilizing peroxyinitrite as a le degrader of lignin during pulp bleaching. This is because the alkoxyl radicals that form suffer a carbon-carbon scission, which implies size reduction of the carbon skeleton in the biopolymer. Coworkers Prof. Sara Goldstein and Prof. Gidon Czapski at Hebrew University, Jerusalem, Prof. Harold Schwarz and Dr. Sergei Lymar, Brookhaven National Laboratories, Dr. Tore Brinck, Dept. of Physical Chemistry, KTH.

STRUCTURE EFFECTS IN PULP BLEACHING Johan Lind and Erik Johansson During ozonation of pulp a radical chain reaction operates. The radicals should not be able to diffuse into the crystalline part of the fibre. Still, depolymerisation occurs to a substantial degree. By product analysis and reaction kinetics a model was postulated. It implies that the initial surface attack on crystalline cellulose leads to a more penetrable structure. In subsequent reaction steps a pit is formed on the fibre. By electron microscopy we have later confirmed the model. Now research is focused wether or not on this mode of operation applies to oxygen and hydrogen peroxide bleaching as well.

FUEL DISSOLUTION Trygve E Eriksen, Mats Jonsson, Kristina Ljungqvist, Maryam Abili Nejad The source term for release of radionuclides from a repository for spent nuclear fuel into the environment is assumed to be oxidative dissolution of the fuel matrix caused by radiolysis of the surrounding groundwater. The objective of the project, which is carried out in cooperation with research groups in Studsvik and Barcelona, is to develop a kinetic model, based on radiolysis, heterogeneous electron transfer and dissolution reactions, for the oxidation and dissolution of irradiated UO2 fuel in aqueous solution. Dissolution studies with highly radioactive fuel fragments are carried out at Hot Cell Laboratory, Studsvik to determine the mass balance for radiolytically generated oxidants/reductants and dissolved uranium. High pressure hydrogen is known to increase the recombination of radiolytically produced reactants and reduction of U(VI) in solution has also been suggested. The dynamics of reduction of U(VI) to U(IV) by H2 is studied within the department and studies of reactions between radiolytically formed radicals and UO2 have recently been initiated. Modelling of experimental data is carried out in cooperation with Professor J.Bruno and coworkers at Enviros QuantiSci, Barcelona.

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Nuclear Chemistry THERMOCHEMICAL STUDIES OF RADICALS IN SOLUTION Mats Jonsson, Johan Almstedt, Magnus Carlsson This project started in May 1997 and it is mainly focused on experimental studies of thermochemical properties of radicals and radical ions in solution using radiation chemical, electrochemical and calorimetric methods. Some topics of special interest are: (1) Substituent and solvent effects on the thermochemical properties of radicals and radical ions in general, (2) Oxidation of peptides/proteins and other biomolecules and thermochemical characterization (e.g. redox and acidity properties) of the radicals formed in these processes, (3) C-O bond dissociation enthalpies and redox properties of peroxyl radicals and O-H bond dissociation enthalpies of hydroperoxides, (4) Thermochemical characterization of potential antioxidants and (5) Development of new techniques for characterization of radicals in solution.

FREE RADICALS IN ENVIRONMENTAL CHEMISTRY Mats Jonsson, Kristina Einarsson, Ella Ekeroth Radical induced oxidation is a possible pathway for degradation of persistent organic pollutants in nature. In this project we study the mechanism and kinetics of OH-radical induced oxidation of PCB:s. Another topic of interest in this recently started project is radical reactions with humic and fulvic acids. So far we have focused on characterization of the radicals formed in the reaction between OH-radicals and humic/fulvic acid in aqueous solution. We plan to continue with studies on radical induced oxidation of metal complexes with humic and fulvic acids.

APPLIED RADIATION/RADICAL CHEMISTRY Torbjörn Reitberger For a number of years we have enjoyed working in collaboration with wood- and polymer chemists in a number of different projects. A common denominator has been radical reaction mechanisms. In wood chemistry radical reactions are involved foremost in bleaching processes. In polymer technology the problems of chemical ageing originate in the radical formation in the materials. Both these lines of research continue in TFR and EU sponsored programs.

ECO-EFFICIENT DELIGNIFICATION (TFR), OXYDELIGN (EU) Torbjörn Reitberger,David Stenman, Magnus Carlsson Background One obvious limitation in oxygen delignification is the low reactivity of oxygen. Only at high temperature and pH the delignification proceeds at a reasonable rate. Under these conditions, however, carbohydrate degradation is inevitable. Therefore, one would like to delignify under milder conditions. This may be reached by ”advanced oxidation technologies”, AOT, using special oxidation catalysts, e.g. enzymes, transition metal complexes, polyoxymetalates and photocatalysts. In contrast to conventional oxygen delignification, AOT-processes do not require high pH and temperature. For this reason the cellulose fiber is expected to be less affected by deformation, ”curl”, and degradation by oxidation and alkaline hydrolysis. The general aim of this project is to increase the efficiency and selectivity of oxygen delignification. In this endeavor we would like to develop selective oxidation catalysts which allow degradation not only of phenolic but also nonphenolic lignin structures otherwise unaffected by oxygen/alkali. Another goal is to elucidate how oxygen delignification acts on the fiber level and to develop means and methods to prevent degradation of the carbohydrates in the (hemi)cellulose part of the fiber. The ideal catalyst does not attack the

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Nuclear Chemistry carbohydrates or generate non-selective radical species. It is either an oxygen atom transfer agent or a clean one-electron oxidant. In order to efficiently oxidize not only phenolic but also non-phenolic lignin structures we assess that the reduction potential of the catalyst has to be > that of chlorine dioxide, i.e. 0.94 V. Results The carbonate radical anion exhibits properties which implies that it may be a possible AOT reagent (reduction potential, environmental aspects, compatibility with existing technology). As a starting point, we have performed pulse radiolysis experiments to measure the reactivity of this radical towards various lignin and carbohydrate model compounds. These studies showed that the carbonate radical anion can oxidize both phenolic and non-phenolic lignin structures as well as glucose, cellobios and methyl-βD-glucopyranoside. The kinetic selectivity for lignin structures is in the range 103-104. Measurements at different pH’s showed that the rates of the protonated and deprotonated forms of both carbohydrates and phenols differed. In this way we obtained ”titration curves”, for the first time seen in carbohydrate compounds. For measurements at lower pH’s another source of the carbonate radical is needed. One method uses peroxynitrite and carbon dioxide to produce the carbonate radical anion. This method will be adapted for product and rate studies at neutral pH’s. It is also applicable in direct pulp treatment.

LONG-TERM PROPERTIES OF POLYMERIC MATERIALS (TFR FRAME PROGRAMME) Torbjörn Reitberger,: Petter Eriksson Background Thermal oxidation of hydrocarbon polymers is often the cause of deterioration of material properties and is an important factor determining the longterm performance of many polymer products. It is also an obstacle to the recycling of plastics and rubber materials. A challenge in the study of polymer degradation has been to develop sensitive techniques to analyze the spatial variation of oxidation present in polymers during the early period of thermal ageing. Oxidative degradation of organic materials is usually accompanied by the emission of extremely weak chemiluminescence due to the formation of excited carbonyl groups. This light can be measured by photon counting. Feasible equipment, including a unique photon counting camera, has been constructed for this research. The camera allows both spatial and temporal resolution providing much better possibilities to study ageing processes on a surface or in small particles Results Using the camera physical spreading of oxidation has been observed in polyolefins. We have also demonstrated that this spreading is partly mediated by the gas phase. By inducing local oxidation, e.g. by UV irradiation in the center of a polymer film, propagating oxidation fronts were observed. By comparing the rates these fronts propagate the performance of different stabilizers could be assessed.

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Organic Chemistry Research and teaching staff: Christina Moberg professor Peter Somfai professor Torbjörn Norin professor emeritus Björn Åkermark professor emeritus Peter Baeckström Ph D Jan Bergman Ph D (professor, KI) Anna-Karin Borg-Karlson, Ph D (associate professor) professor 2, NTNU, Norway Styrbjörn Byström Ph D (associate professor) Jonas Hellberg Ph D (associate professor) Ulla Jacobsson Ph D (associate professor) Christian Linde Ph D Mats Svensson Ph D Sture Strömberg Ph D Rikard Unelius Ph D (associate professor) Krister Zetterberg Ph D (associate professor)

Administrative and technical staff: Henry Challis Jan Olov Lindström Ingvor Larsson Lena Skowron

lab. technician lab. technician secretary secretary

Organic chemistry is a fundamental science dealing with the synthesis and reactions of organic compounds, the investigation of their properties and the relationships between their molecular structures, interactions and functions. The role of organic compounds and reactions in industrial processes is well recognized and numerous applications exist. The teaching and research activities of our section are therefore rather broad and some applied aspects are also part of the programme. Asymmetric catalysis, organic synthesis, natural product chemistry, bioorganic chemistry, and ecological chemistry are the principal research areas. The research is mainly of fundamental nature but there are also research projects of applied character carried out in collaboration with industry. The research may be summarized in brief as follows: • The function and use of transition metal catalysts in organic synthesis. • New selective synthetic methods using organometallic reagents. • Synthesis of complex organic compounds of biological, pharmaceutical or technical interest. • The use of enzymes in organic synthesis – scopes and limitations. • Natural product chemistry including studies of biologically active compounds of natural origin. • Ecological chemistry – analysis of biologically active compounds in insect/ insect and insect/plant relationships. • Molecular recognition and interactions – studies on structure/activity relationships using experimental methods and molecular modelling. • Synthesis and properties of specialty chemicals such as electro- and magnetoactive organic materials, surfactants, and colloids. • Computational chemistry.

ADVANCED UNDERGRADUATE TEACHING • Organic chemistry I, (3B 1510, fortsättningskurs, 10 credits) • Organic chemistry I, for B.Sc. students in chemistry (6D 2941, 4 credits) • Organic chemistry II, for B.Sc. students in chemistry (6D 2943, 4 credits) • Diploma work (3B 1005 and 1015) Members from Organic Chemistry have also participated in the teaching of six undergraduate courses for the chemical engineering students (School of Chemistry, Chemical Engineering and Biotechnology and KTH College of Engineering) as well as a course in general chemistry for the School of Civil Engineering. Staff members of Organic Chemistry have taken active part in the development of Master and PhD programmes in Organic Chemistry in developing countries (Moçambique and and Sri Lanka). These development actions have been sponsored by SIDA/SAREC.

GRADUATE SCHOOL Registered and active graduate students 45 (incl. visiting and external students) Dissertations 6 PhD (tekn dr) 2 Tekn lic

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Organic Chemistry Graduate courses The following courses have been given: • On-line literature search, optional course for graduate students in chemistry and chemical engineering (2 credits) • Research frontiers in organic chemistry (3 credits) The course is continuously going on with literature seminars once a week and research seminars (see below) • Methodology in research (compulsory graduate course for all students in chemistry and chemical engineering, 3 credits) • Organic stereochemistry (4 credits) • Stereochemistry for chemical engineers (1 credit) • Preparative separation methods for organic chemists (2 credits) • New trends in organic chemistry (2 credits) • Spectroscopic methods in organic chemistry (3 credits) • Chemical engineering for chemists (1 credit)

Graduate research work The registered graduate students are carrying out their PhD-work as members of research groups of the organic chemistry division (24) or as external students performing their research work at an industrial laboratory, research institute or the University College of Mid Sweden (Mitthögskolan).

RESEARCH SEMINARS Research seminars have been given by 10 visiting scientists from various parts of the world. The seminar activities also include presentations of current research work by members of the organic chemistry division and presentations of diploma work carried out by undergraduate students. Professor Gregory C. Fu from Department of Chemistry at MIT in Boston has been invited as the second speaker in the special seminar series in the honor of late professor Holger Erdtman. He gave the lecture “Asymmetric catalysis with ‘planar-chiral’ heterocycles.” Part of his visit was also devoted to discussions with our graduate students.

PRESENTATIONS OF RESEARCH AND TEACHING ACTIVITIES An important task of the division of organic chemistry is to inform various groups of the society about the research and teaching activities and to transfer knowledge to industry and society. The division has been actively engaged in several arrangements for these purposes. Thus members of our division have been engaged in the “Berzelius days”, organized by the Swedish Chemical Society, for high school students (380 students and 120 teachers from all parts of Sweden). The organic chemistry division is also engaged in a summer school for high school students. The transfer of knowledge to industry is mainly performed via research projects sponsored by NUTEK. Our industry partners continuously receive information from the research groups and take part in project meetings.

Graduate students: Fredrik Andersson Fredrik Allared Oscar Belda Jan Blid Ulf Bremberg Emma Dahlstedt Helen Edlund Carina Eriksson Hans Frykman Jenny Fäldt Kristina Hallman Björn Hedman Jan Holmbäck Dan Isaksson Staffan Karlsson Fredrik von Kieseritzky Daniel Koch Fredrik Lake Abraham Langlet Michael Larsson Marica Lindmark Charlotta Lindquist Mona Lindström Rong Liu Raimondas Mozuraitis Ba-Vu Nguyen Christina Jönsson Kristina Neimert Andersson Berit Olofsson Felisberto Pagula Monika Persson Peter Piispanen Fredrik Rahm Per Renström Erik Risberg Didier Rotticci Ellen Santangelo Åsa Sjöholm Olof Smitt Robert Stranne Carina Svensson Anh Tran

RESEARCH The research is carried out on different but more or less interrelated research projects. Organic synthesis and natural product chemistry are the principal lines. An important area of the research is the development of selective methods for synthesis of organic compounds of biological, pharmacological, physical or chemical interest. The research also deals with reaction mechanisms as well as the stereochemistry and dynamics of those organic molecules. Molecular modelling is an important tool in these research activities. Another general line of research, which is becoming an important topic, is studies of molecular recognition and interactions in relation to catalysis, Page 23

Organic Chemistry

Visiting scientists (>1 month visit): Darshika Akiyasena Maria Fusto Patrick Kelly Uttam Khamrai Sacha Legrand Ilme Liblikas Serguei Lutsenko Patrice Marchand Colin Ray Heimo Schmitt Jean-Luc Vasse Roel Wijtmans Annie Yart

Sri Lanka Italy US India France Estonia Kazakhstan France Great Britain Germany France Netherlands France

enzyme/substrate and receptor interactions as well as surface phenomena, such as adsorption and self-assembly (supramolecular chemistry). Research in this interdisciplinary area is carried out in collaboration with theoretical chemists, biochemists, biologists, molecular biologists and physical chemists. Molecular modelling is an important tool in these research activities. Current research topics can be summarized under the following headings: • New selective synthetic methods using organometallic reagents. • The function and use of catalysts (organic, organometallic, bio-organic) in organic synthesis. • Synthesis of complex organic compounds of biological, pharmaceutical or technical interest. • Natural product chemistry including studies of biologically active compounds of natural origin. • Molecular interactions and studies on structure/activity relationships, molecular modelling. • The use of enzymes in organic synthesis, scopes and limitations. • Specialty chemicals and products including electro- and magnetoactive organic materials, reagents, surfactants, and colloids – syntheses and properties. • Analysis of biologically active compounds in insect – plant relationships, especially enantiomeric separation.

RESEARCH PUBLICATIONS AND PARTICIPATION IN SCIENTIFIC MEETINGS Apart from official reports to various research councils and short articles in Swedish journals and newspapers, 20 scientific papers have been published in international journals during 2000. In addition 6 PhD-theses and 2 Lictheses have been produced. The publications are listed in the appendix. Staff members and graduate students of the division of organic chemistry have participated in a number of international scientific meetings in different parts of the world (invited lectures, short communications and poster presentations).

SHORT PRESENTATIONS OF THE RESEARCH GROUPS Terpenoid synthesis and separation techniques Peter Baeckström Synthesis. Transformations in terpene chemistry e g photooxidations with simultaneous oxidation and reduction, allylic rearrangements and isoprenoid chain elongation. During year 2000 Felisberto Pagula from Moçambique has been engaged in this type of work. Separation techniques. Developing efficient methods for liquid adsorption chromatography has been a longstanding investigation to enable efficient separations of large amounts of synthetic mixtures or extracts of natural products. The task was originally undertaken with the slogan “Minimum Effort Liquid Chromatography.” By studying the effect of different types of gradient elution, and emphasizing column length (amount of adsorbent) as a crucial parameter, solvent, adsorbent and time consumption have been drastically reduced compared to conventional methods. A program that will minimize time or cost for a given separation has been written in MS Excel. The isolation of azadirachtin from seeds of Azadirachta indica, the most potent naturally occurring insecticide known at present, has been used as a model for group separation of

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Organic Chemistry compounds by combined extraction and chromatography in columns loaded with seeds mixed with silica. The results of this project clearly indicates that percolation with solvents or Soxhlet extraction can be bypassed for relatively dry plant material. Our methodology, has been presented at numerous workshops on separation techniques. Most of these, sponsored by SIDA-SAREC, IFS and IPICS, have been held in developing countries. During 1999 two workshops were held, one in Sri Lanka and the second in Botswana. Further, three students from developing countries, two from Sri Lanka (sponsored by IPICS) and one from Nigeria (sponsored by the Swedish Institute), have been accepted for training and participating in further developing the techniques. During year 2000 the methodology of combined extraction and group separation was extended to the isolation of glycosides directly from the wet pulp of the palmyra fruit. This work was conducted in cooperation with Darshika Akiyasena from Sri Lanka, sponsored by IPICS, Uppsala University. During the fall semester of year 2000 a course in methods for optimizing preparative chromatography using silica gel was given for the PhD students at KTH.

Premises: Modern research and teaching laboratories and offices in relatively new and reconstructed buildings.

Equipment: Advanced spectroscopic (NMR, MS, GCMS, IR and UV) and chromatographic (GC, LC and HPLC) instruments and equipment for distillation. Equipment for research work under inert atmosphere. Computer facilities and advanced equipment for molecular modelling.

Ecological chemistry Anna-Karin Borg-Karlson, Torbjörn Norin and Rikard Unelius The research is focused on the structural determination and biological activity of insect and host – plant related compounds, e g separation, identification and synthesis of chemical signals released by living organisms. The biological significance of the compounds, that constitute the signals, is evaluated in close collaboration with biologists. By combining experience in analytic and synthetic organic chemistry as well as in entomology, ethology, biochemistry, microbiology and polymer technology we can reach one of the main goals: to replace the use of insecticides with environmentally friendly ecochemicals (green chemicals) for monitoring and control of insect pests. Part of the research is organised in the inter-disciplinary program, ‘’Pheromones and Kairomones for Control of Pest Insects,’’ financed by MISTRA (Foundation for Strategic Environmental Research, Stockholm, Sweden). Other parts of our research is financed by two EC-projects with the participation of forest entomologists, physiologists and ecologists from China, France, Spain, Portugal, Finland and Sweden. Visiting scientists from the Baltic region are engaged in these projects. They are financed by the Swedish Institute within the program “Ecological chemistry and the control of insect pests”. Host-plant related compounds and their biological activity Pine and spruce. Terpenes are important as signalling compounds in insect – plant interactions. We are studying the composition of volatile terpenes of host trees to be able to correlate insect attraction to healthy as well as stressed pine trees from China and Europe. These studies will allow us to predict factors affecting the susceptibility and resistance in conifers. We are also analysing, by 2D-GC and GC/LC-MS techniques, the dynamics of the fungi-induced chemical defence in infested trees. The expression of monoterpene synthases in different tissues of the trees can be estimated by correlating the relative amounts of monoterpenes to each other. Butterfly plant-derived pheromones. A new class of aromatic insect pheromones has been identified by using SPME (Solid Phase Micro Extraction).

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Organic Chemistry By 13C labelling experiments, we have shown that aromatic amino acids are precursors for the “antiaphrodisiac” compound transferred to the female by the male during copulation, and then emitted by mated females.

Figure 1. The male butterfly, Pieris napae, approaches a mated female showing the typical signalling posture.

Pine weevil. Antifeedant compounds derived from conifers are identified, synthesised and their biological effect has been evaluated using behavioural tests. The work has been performed in collaboration with forest entomologists at the Swedish University of Agriculture (SLU, Uppsala). Three patent applications have been filed on this topic. The compounds will hopefully replace the presently used insecticide permetrin, which will become an important step towards sustainable forestry. Biologically active host – plant constituents in moths The use of host – plant compounds in combination with pheromones is a promising tool for the control of the codling moth Cydia pomonella, the major pest on apple. The research is focused on isolation, characterisation, and synthesis of host – plant compounds. Similar research is also carried out on the economically important polyphagous moths Helicoverpa armigera and Heliothis virescens (in collaboration with a research group in Trondheim). An important technique for determining biological activity of plant constituents is to measure the electrophysiological responses of antennal odour receptor neurons. The sesquiterpene germacrene D, E,E-α-farnesene, and a large number of aliphatic “apple” and “pear” esters are evaluated by EAG (ElectroAntennoGraphy), in wind tunnel bioassays and in field tests using males and females of C. pomonella. By using a chiral column in combination to single cell recordings, the selectivity to the germacrene D enantiomers has been determined in H. armigera and H. virescens. In cooperation with the neurobiologists at the Freie Universität in Berlin, the reception of host-plant compounds has been tested in insects. The location and pattern of the neuronal activity in the brain is measured and found to be characteristic for each odour. Bioremediation Cooperation with groups at KTH and Stockholm University, working with environmentally related topics, has been established. Microbial degradation of diesel, aliphatic hydrocarbons, polyaromatic hydrocarbons and phenols as well as constituents in bitumen and related materials and trapping of chlorinated organic solvents are studied mainly by GC-MS. The new concept, with repeated sampling during the degradation process using SPME, is found to be effective.

Synthesis and properties of electroactive organic materials Jonas Hellberg Organic compounds as electrical conductors are a relatively new phenomenon. Cation radical salts of electron-rich aromatic donors belong to a class of compounds where metallic conductivity and even superconductivity can be found. Our group is studying the synthesis and properties of these fascinating materials. Most systems are based on a tetrathiafulvalene, thiophene,

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Organic Chemistry or dibenzodioxine core; examples of structures synthesized are shown in Figure 2. Our group is also engaged in the modification of these systems to self-assembly and Langmuir-Blodgett amphiphiles, for use in thin-film applications for molecular electronics, e g amorphous organic transistors. We are also studying the effect of chalcogenation substitution on the light-emitting diode (LED) properties of polythiophenes.

O

O

O

O

O

O

O

O C10H22

C10H22

S

S

Figure 2. Examples of electron-rich aromatic donors. S

Catalytic oxygenation reactions

HS

S

S

S

S

S

S

(CH2)n

HS

S

S

S (CH2)n

Christian Linde The development of an efficient catalytic system for aerobic oxygenation reactions remains a great challenge in chemistry of today. Several biological systems, e g cytochrome P-450, are able to convert hydrocarbons to alcohols by using dioxygen as the terminal oxidant. These systems generally require a sacrificial reductant to deliver the electrons and protons needed to complete the catalytic cycle. Single-oxygen transfer agents, e g iodosobenzene, peracids, peroxides, N-oxides and hypochlorite are therefore used by chemists in order to avoid the need for stoichiometric amounts of co-reductant. However, these oxidants are either expensive or produce stoichiometric amounts of the reduced form of the oxidant as a byproduct. The generation of active single-oxygen transfer species directly from dioxygen which could transfer both oxygens to e g an alkene would therefore be desirable especially for industrial applications. O=M

(n+2)+

2Mn+ + O2 ➝ 2 O=M(N+2)+ + alkene ➝ Mn+ + epoxide

Our research is focused upon the study and development of ruthenium complexes for catalytic aerobic oxygenation reactions. There are some properties of ruthenium that makes it a promising candidate for this purpose. There are several oxidation states on ruthenium, which are reversibly accessible. Stable oxo-ruthenium species are known, [RuVI(O)2 and RuIVO], which do transfer oxygen to e g alkenes. Indeed, there are also a few examples of ruthenium catalyzed oxygenation reactions where dioxygen is used as the oxygen source without the aid of a coreductant. These systems all work catalytically but reaction rates are extremely slow and product selectivity is often poor. We are using both experimental and theoretical methods in collaboration with Dr. Mats Svensson, KTH, in order to investigate these systems and to design new complexes that are able to catalyze the reaction with increased efficiency. An additional goal is to develop stereoselective catalysts for these reactions.

Transition metal catalysis in selective organic synthesis Christina Moberg Access to synthetic methods allowing the preparation of chiral compounds is highly important as such compounds are needed for a variety of applications, including the production of pharmaceuticals, flavors, fragrants, food additives etc. By the use of chiral transition metal catalysts, large amounts of chiral compounds can be prepared using a small amount of the metal compound. Asymmetric metal catalysis is therefore a strongly expanding area within the field of organic chemistry. Our research deals with the investigation of transition metal-catalyzed processes and the study of metal complexes and their interaction with orPage 27

Organic Chemistry ganic molecules. It involves the areas of catalysis, organometallic chemistry, coordination chemistry and host guest chemistry. The general aim of our studies is to develop new chemo-, regio- and stereoselective (particularly enantioselective) processes for application in organic synthesis. The work involves the design and preparation of new ligands for use in stereoselective processes. In the design of the new ligands and metal complexes, particular attention is devoted to the steric, electronic and symmetry properties of the compounds. One type reaction that has been studied by our group is the palladiumand molybdenum-catalyzed substitution of allylic acetates and carbonates. The reaction is synthetically highly versatile as it allows the formation of carbon-carbon as well as carbon - heteroatom bonds with high regio- and stereoselectivity. For the molybdenum-catalyzed process a new catalyst, yielding the product with higher stereoselectivity than previously published catalysts, has been prepared. The reactions, where this catalyst as well as some catalysts containing palladium are used, have been shown to be accellerated by microwave irradiation, which allows complete reaction within a few minutes without loss of selectivity, see Figure 3.

O

O NH HN

MeO

O Ph

O

N

O N

OMe

OMe

MeO

O

O OMe

Ph 4% Mo(CO)6 , CH2(CO2Me)2, CHNa(CO2Me)2, BSA THF, µ-waves, 5 min

93% >99% ee

+

MeO

O OMe

Ph 2%

Figure 3. Microwave-mediated enantioselective molybdenum-catalyzed allylic alkylation.

In one project chiral ligands with rotational symmetry, in particular with C2 and C3 symmetry, are studied in catalytic applications. Furthermore, chiral ligands containing additional groups capable of supramolecular interactions with the reacting substrates are prepared and investigated in catalytic processes. To allow recovery and use of the often expensive ligands and metal catalysts, methods for grafting the catalysts on polymeric supports are being developed. Within the framework of an SSF programme (the Swedish Foundation of Strategic Research) on nanochemistry, a collaboration with the instrumentation laboratory at the Department of Signals, Sensors and Systems, KTH, was initiated. One aim of the project is to develop microdevices for catalytic reactions. Such devices are useful e g for combinatorial chemistry. So far, chiral metal complexes have been bound to silica chips. The chips are presently tested for catalytic applications.

Figure 4. Part of the active site of Rhizomucor miehei lipase showing the water channel ending at the carbonyl carbon of the acyl enzyme intermediate.

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Organic Chemistry Biocatalysis and natural product chemistry Torbjörn Norin Studies of enzyme properties and of enzyme/substrate and enzyme/solvent interactions are current research topics, which are carried out in close collaboration with theoretical chemists of our department as well as with biochemists of the Department of Biotechnology. Methods for asymmetric synthesis and in particular the use of enzymes for this purpose are important goals of our program. Simulation models (molecular modelling) and a computational approach have been developed for prediction of selectivity and for enzyme modification by protein engineering. Focus has been on the detailed catalytic mechanism and dynamics of hydrolytic enzymes such as lipases and esterases. The geometries of the transition states of the hydrolytic reactions have been calculated. Water assisted catalysis and the role of water in these systems have been studied (Figure 4 and 5). The docking modes of substrates of secondary alcohols have been calculated and provide good models for the prediction of enantioselectivity [for references see F. Hæffner and T. Norin, Chem. Pharm. Bull. 1999, 47, 591]. Site-directed mutagenesis has been applied to improve the enantioselectivity of a lipase catalyzed reaction (Candida antactica lipase B). N

Ser

O

H

–

Asp

O

O H

H

N

R2

N

H N

Figure 5. A hypothetical 6-membered ring transition state of a water

–

O

H O +

H

R1

O

His

assisted enzyme catalyzed ester hydrolysis reaction.

Development of new methodology in organic synthesis Peter Somfai The focus of our research efforts is efficiency in organic synthesis and various aspects of this can be readily identified. For example, the yield of a given reaction, its environmental friendliness and cost efficiency, if it can be converted into a catalytic process or, alternatively, into an asymmetric one are all important issues that have to be considered when choosing a suitable reaction for affecting a desired transformation. We are mainly interested in developing new methodology in organic synthesis with the intention of applying the chemistry for the total synthesis of natural products. Presently, we are interested in finding new routes to scalemic vinylaziridines and study their selective ring expansions, develop a regio- and stereoselective synthesis of vic-amino alcohols, and investigating the intramolecular cyclization of cationic aminyl radicals. These projects are summarized below. 1. Ring-expansion in vinylaziridines Vinylaziridines are useful intermediates in organic synthesis. We have recently developed a novel entry to NH vinylaziridines and shown that these substrates can be selectively ring expanded to the corresponding 6and 7-membered heterocycles, respectively, in good yield and excellent selectivity (Figure 6). We are cur-

O N

KHMDS

R

NH

Aza-[3,3]-Claisen rearrangements

≥75%

R

N H

O

R

N H

CO2t-Bu

R CO2t-Bu N R

Aza-[2,3]-Wittig rearrangements

LDA ≥90%

Figure 6. Ring-expansion in vinylaziridines.

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Organic Chemistry rently investigating the scope and limitations of these transformations, and we are also applying them as key steps in the synthesis of alkaloids. 2. Stereodivergent synthesis of vic-amino alcohols 1,2-Amino alcohols represent a structural subunit common to several biologically active compounds as well as to auxiliaries and ligands for asymmetric synthesis. Although large efforts in developing efficient routes leading to vic-amino alcohols have been made, no general route towards all eight possible isomers (regioisomers included) has been presented. The development of such a route would be ideal for obtaining structure – activity relationships for pharmacologically active derivatives incorporating this structural motif and for optimizing the performance of chiral ligands containing this substructure. NH2

OH

R

R NH2

OH

R

OH

NH2

O

R

R

NH2

OH

Figure 7. Synthesis of vic-amino alcohols from a vinylepoxide.

We are developing a general and stereodivergent route to all possible isomers of vic-amino alcohols starting from vinylepoxides, that can be readily synthesized (Figure 7). The chosen synthesis route leads to four isomers of the vic-amino alcohol, the remaining four isomers can be obtained by starting with the enantiomeric vinylepoxide. 3. Intramolecular cyclization of cationic aminyl radicals N-Chloroalkenylamines can be cyclized into the corresponding pyrrolidines under acidic, photochemical or metal-catalyzed conditions (Figure 8). We are investigating the inherent diastereoselectivity of this reaction with the aim of developing an enantioselective version.

H ( )n

N

Cl NCS R

( )n

N

( )n

M R

N

H2O/AcOH Cl

R

n=1, 2, 3 M=TiCl3, FeCl2/FeCl3, CuCl/CuCl2

Figure 8. Metal-catalyzed cyclization of N-chloroalkenylamines.

Theoretical studies of organometallic reactions Mats Svensson Computational based chemistry is a fast growing research field both in the academic world and in the industry. The speed of modern workstations together with the development of more efficient methods and algorithms have made computer-based chemical research an interesting complement to experimental chemistry. As a confirmation, the 1998 Nobel prize in chemistry was awarded to two quantum chemists, John Pople and Walter Kohn. Our main interests concern the chemistry involving transition metals as catalysts. This is a field particularly well-suited for a theoretical study since many of the intermediates are hard to isolate under normal experimental conditions. Page 30

Organic Chemistry We are working in close collaboration with experimental groups in our department and at other universities. The goal is an increased understanding of the electronic and steric effects governing the reaction profiles of organometallic reactions. Projects presently under study are: • Epoxidation of alkenes catalyzed by manganese-salen complexes. This is an in house collaboration in the organic chemistry group at KTH, Dr. Christian Linde, together with professor Björn Åkermark, StockEnergy holm University, and assoc. professor Per-Ola Norrby at the Royal Danish School of Pharmacy. The theoretical part of Late spin transition Intermediate formed this project is aiming for an understanding of the mechanism quintet Isomerization governing the isomerization and the selectivity of this importriplet tant epoxidation reaction. The reaction is a two-state reaction in which the spin changes from triplet to quintet. The timing Early spin transition of the spin-flip is believed to be important for the amount of No intermediate formed No isomerization cis-trans isomerization (see Figure 9). O•

Mn•

•

O

Mn

•

O

triplet

•

Mn

O Mn

quintet

Figure 9. The potential energy profile for the Mn(salen) catalyzed epoxidation of alkenes.

reaction co-ordinate

• Late transition metal complexes as catalysts for olefin polymerization. The initial steps, the π-complexation and migratory insertion of the olefin into the metal-alkyl bond is studied in detail in order to understand the influences of the substituent on the olefin and the role of the metal. This is a very promising reaction for the development of new polymers; a collaboration between Dr. Krister Zetterberg and Dr. Staffan Strömberg. • Regiocontrol in the Heck reaction. A combined theoretical and experimental study of ligand and substrate effects on the regioselectivity in the Heck reaction using the biphosphine ligands dppe and dppp; a collaboration with professor Björn Åkermark and Henrik von Schenck. • Nitrogen fixation by nitrogenases. We have studied the fixation of nitrogen, step by step using Fe2 and Fe4 models for the active site in the nitrogenase. This projects is a collaboration with professor Per Siegbahn and Joakim Westerberg, Stockolm University, and professor Robert Crabtree, Yale University.

Transition-metal catalysis and olefin polymerization Krister Zetterberg In its simplicity, the straightforward association of an alkene to a ␶-alkyl transition metal and the following migratory insertion (M.I.) represent a part in common for some, in all respects, very productive organic reactions catalyzed by transition metals. Actually, this short sequence can summarize the process of strategic scale transition metal-catalyzed polymerization of alkenes. Despite the importance of this process and the vast research caused by it, there still remains an uncomfortably large number of chemical questions to be settled. These important questions are to be answered by research in the field of fundamental organometallic chemistry. Our research is especially devoted to the chain-building step, the migratory insertion. The experimental studies are combined with ab initio calculations, the latter in cooperation with Mats Svensson at our division. Our efforts will concentrate on calculations combined with experimental work. Page 31

Physical Chemistry Research and Teaching Staff: Mikael Björling Eva Blomberg Tore Brinck István Furó Ulf Henriksson Peter Stilbs William Price

Ph.D Ph.D Ph.D, associate professor Ph.D, associate professor Professor Professor Ph D, Visiting Scientist

Administrative Staff: Marianne Ericsson

Administrative secretary

In an international perspective, Physical Chemistry is a very wide subject. The research activities of Physical Chemistry at KTH primarily focus on problems related to surfactant and polymer systems in aqueous solution and in the liquid crystalline state, mainly using tools like Nuclear Magnetic Resonance (NMR), theoretical modelling by thermodynamic and statistical-mechanical methods and direct surface force measurements. There are also long-term efforts with regard to methodological and instrumental development in solution. A newly started research branch concerns modelling and prediction of quantitative molecular structure-activity relationship (QSAR), as based on quantum chemical calculations. ADVANCED UNDERGRADUATE TEACHING Quantum Chemistry and Spectroscopy (3B1211, 6 credits) Statistical Thermodynamics (3B1222, 4 credits) NMR-Spectroscopy (3B1231, 4 credits)

Graduate Teaching All advanced undergraduate courses are also available for graduate students.

Research Seminars Research Seminars have been given by about 5 visiting scientists from various parts of the world.

PRESENTATION OF AND INFORMATION ON RESEARCH ACTIVITIES Studies of Molecular Transport Order and Local Dynamics by Nuclear Magnetic Resonance (NMR) Methods Peter Stilbs NMR methods of various kinds can provide a detailed quantitative picture of the title phenomena, especially in solution, where the techniques are selectively applicable to individual constituents in quite complex systems. In particular, the research of the group has been focused towards the development and application of magnetic field gradient methods for studying the self-diffusion of individual constituents in solution systems. Typical applications concern surfactant and polymer systems, and it is very straightforward here to deduce information about binding phenomena and molecular ordering from such data - information that is not readily accessible in any other way. Measurements of nuclear spin relaxation provide information about local dynamics of molecules – data that in many ways can be regarded as complementary to the self-diffusion information. Activities have also been started also with regard to electrophoretic NMR, characterisation of porous systems by NMR and NMR microscopic methods for studying flow. At present, the department has three spectrometers with partly unique attachments for the mentioned tasks. A few years ago we also started work on a general computer procedure for global analysis of correlated spectral data sets. The method has been named CORE. It is not limited to NMR and has also been applied to images. For further info and references, consult the homepage: http://omega.physchem.kth.se/~peter/.

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Physical Chemistry Ulf Henriksson The molecular dynamics and organisation in systems containing surfactant aggregates of different sizes and shapes are studied by NMR methods with special emphasis on the occurrence and properties of aggregates with shape and different from the classical spherical, circular, cylindrical and lamellar. In isotropic systems (micellar solutions and cubic liquid crystalline phases) frequency dependent relaxation is used and in other liquid crystalline phases the aggregate symmetry is studied mainly by line shape analysis. The following main problems are addressed: The effect of solubilization on micellar phase shape, size distribution and internal structure of the micelles. Aggregate structure in the micellar phase that surrounds the hexagonal phase in the decylammonium chloride-water phase diagram. The occurrence of disk-shaped micelles.

The molecular dynamics of alkyl chains in different structures. István Furó Three main research directions are pursued by us: we develop new NMR methods, apply them to study some basic aspects of complex fluid systems, and use them to solve some industrially relevant problems. On the methodology side, we build new instruments and design new NMR pulse sequences. The goal is to be able to measure previously inaccessible NMR parameters, which then can be used to understand the molecular structure and dynamics of systems like micelles, lyotropic liquid crystals, polymer-surfactant mixtures, gels, porous materials. One particular direction is to create a non-equilibrium state of the sample within the NMR probe and then to study the evolution of the sample by NMR spectroscopy. Two equipments for this purpose are concentration-jump and temperaturejump NMR probes. One area of our basic studies is phase transitions in lyotropic liquid crystals. These complex fluids are built up by surfactant aggregates and the phase transitions are thought to proceed through defects of the original structures. Since the defects are irregular and few, it is difficult to study them by traditional structural methods such as X-ray scattering. We look instead at the diffusion of the surfactant molecules; this is methodologically difficult but often rather informative about the nature and concentration of the defects. It turns out that the NMR methods and expertise that is developed by us in pursuing our basic research goals can be well applied to solve some industrially relevant problems. One such example is studying the pore structure in paper and paper coating in cooperation with the Institute of Surface Chemistry (YKI). The method is NMR cryoporometry where the pore size distribution is obtained by recording the melting of ice confined in small pores. The projects involve a bit of everything: chemistry, physics, electronics. Correspondingly, the personnel includes chemists and physicists.

Registered and Graduate Students: Helena Bergman Peter Carlqvist Britta Folmer Niklas Hedin Kim Paulsen Erik Pettersson Maria Törnblom Ruslan Sitnikov Dulce Vargas

Visiting Scientists: Sergei Dvinskikh Martina Bittererova Cecile Vigouroux, Hans Evertsson Rustem Valiullin Pavel Yushmanov

Russia Slovakia France Sweden Russia Russia

Association and Solution Properties Studies Using NMR William S. Price Whilst at KTH I have been involved in a number of projects as detailed below. In addition I was instrumental in troubleshooting some causes of instability in pulsed gradient spin-echo (PGSE) NMR measurements of translational diffusion on the AMX 300 spectrometer and also in implementing PGSE measurements on the DMX 500. PGSE diffusion studies of salicylate binding to bovine serum albumin PGSE NMR measurements have been used to studying the binding of sali-

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Physical Chemistry cylate with bovine serum albumin and the results compared with previously reported findings for the binding of salicylate to human serum albumin. NMR water suppression techniques Two modes of water suppression have been developed. The first relies on a radiation-damping-assisted selective pulse before gradient spatial encoding to suppress the water resonance. This method is particularly suitable for samples containing very high molecular weight solutes. The second method is an extension of the WaterGate sequence which allows accurate diffusion measurements of solutes at low concentration in aqueous solution. Background gradient and radiation damping effects on PGSE measurements In order for PGSE measurements to completely supplant competing diffusion measuring techniques, its precision and reproducibility needs to be increased. To this end we have experimentally investigated the effects of macroscopic background gradients and radiation damping effects on PGSE measurements and how these deleterious effects can be minimized experimentally. Effects of violation of the short gradient pulse limit on PGSE diffraction experiments The assumption of infinitely short gradient pulses is often invoked to simplify the mathematical models used for describing PGSE measurements on restricted geometries and only recently have theoretical attempts been made to explore the effects of finite length pulses. We have been concerned with conducting experiments on a model system consisting of water diffusing between planes to provide experimental validation of the theoretical approaches so far presented. 17

O PGSE and relaxation measurements of isolated water molecules The translational diffusion and the reorientational correlation times of isolated water (H217O) molecules dissolved in nitromethane were studied using 17O NMR PGSE and relaxation. The results showed that the absence of hydrogen bonding to nearby water molecules significantly affects the translational and rotational motions of water. PGSE measurements of the time-dependence of protein aggregation Aggregation is an essential, but poorly understood, step in protein crystallization. We have demonstrated using lysozyme that PGSE diffusion measurements can provide complementary information to that obtained from traditional techniques (e.g., light scattering) on the time-dependence of the aggregation process. Conducting Electrolyte Systems Multinuclear PGSE diffusion measurements were used to elucidate the ionic conductance mechanisms in lithium salt – polyethylene oxide gel electrolyte systems. Supercooled 2H2O diffusion To deepen our understanding of the water-to-ice transition and to better understand the anomalous properties of supercooled water, PGSE diffusion measurements were performed on supercooled heavy water (2H2O) down to 244 K. The results are summarized in the figure below. Figure 1. An Arrhenius plot of the diffusion coefficients for 2H2O (n). The results of regressing the Vogel-Tamman-Fulcher (____) and Fractional Power Law equation (- - -) onto the data is also shown. (modified from J. Phys. Chem. B. 104, 5874-5876).

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Physical Chemistry Quantum Chemistry Tore Brinck The common theme for the research is the analysis of chemical reactivity and intermolecular interactions in chemical and biological systems using ab initio and density functional theory (DFT). In particular, we have in recent years focused much of our efforts on studying the catalytic mechanisms for hydrolytic reactions in enzymes and in aqueous solutions. As a continuation of this project, we are now studying how hydrolytic enzymes, such as lipases, can be modified by site-directed mutagenesis to catalyze new unnatural reactions. In this work we are combining quantum chemical calculations with molecular dynamics simulations to get a better understanding of the catalytic machinery in the enzymes. These studies are conducted in close collaboration with biochemist and molecular biologist at Biochemistry KTH. We have also recently begun studies on the catalytic mechanism of glutathione peroxidase, a selenium containing enzyme that catalyze the degradation of peroxides. Another area of research concerns the reactivity and properties of isomers of the N4 molecule. Theoretical studies indicate that particularly the tetrahedral form of N4 should be stable and very high in energy content. This molecule, if synthesized, would be very interesting for energy storage and for use as fuel. We are using high level ab initio methods to characterize its excited state properties. The objective is to find electronic transitions that are acessible by laser spectroscopy and therefore can be used for detection. In this work we are collaborating with an experimental group at FOi.

Statistical Mechanics for Polymer and Colloid Systems Mikael Björling Good theoretical models of colloid and polymer solutions are useful in understanding complicated binding and association phenomena. The emphasis has been on surface active polymers in presence of particle interfaces and related subjects such as steric stabilization, flocculation, self-assembly, networks and adhesion. Polymer networks induced by the binding of ligands (surfactants, and or, multivalent ions) has also been studied both theoretically and experimentally (NMR, DLS). Recently a theory of charge fluctuations in micro-emulsion droplets was presented. Ongoing work also include phase separation in asymmetric hard-sphere mixtures and molecular dynamics simulations of simple point-charge models of molecules.

O

O

O O

C

Figure 1. Computed transition state structure for aldol condensation in a model system of the

C

C

reaction center in a mutant of Candida antarctica lipase B.

C

C O

C

N C

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N

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O C

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Surface Chemistry Research and Teaching Staff Magnus Bergström Eva Blomberg Per Claesson Mark Rutland Jan Christer Eriksson

Ph.D. Ph.D. Prof. Ph.D. Prof. Em.

Administrative Staff Marianne Eriksson

Secretary

Surface chemistry is a subject that is important in a range of technologies. It has thus been natural to establish several joint projects with other divisions within the chemistry department, other departments at KTH, as well as with the Institute for Surface Chemistry (YKI). Over the last years, the collaboration with YKI has increased due financial support from the KK foundation. Members of all the sections of YKI are involved (Forest Products, Materials and Coatings, Pharmaceuticals and Food, Chemical and Engineering Industries), which has lead to a very broad and successful range of collaborations. Topics include block copolymers as foam stabilisers, steric interactions in non-polar media and frictional interactions in paper and model systems. Surface chemistry deals with chemical processes at the interface between two phases and the special properties of colloidal systems. Nearly all technical applications within chemistry, from production of paper and ceramic materials to development of novel environmentally more friendly surfactants and biomedical applications, require surface chemical considerations. In this sense surface chemistry is truly a cross-disciplinary research area. The common feature is the importance of surface modification, surface characterisation, adsorption, wetting, adhesive and long-range surface forces. One important research area for the division is fundamental surface chemical problems related to interparticle and intermolecular forces, as well as to adsorption and structures of adsorbed layers of surfactants, polymers, polyelectrolytes and proteins. For these studies a unique set of instruments are employed to measure interactions between surfaces at molecular separations. Three different techniques are used to study interactions between solid surfaces. A fourth technique allows interactions to be measured across liquid films between liquid/air interfaces and between a liquid/air interface and a solid/liquid interface. Combining this battery of techniques, which individually access different experimental parameters, all the forces governing adhesion, colloidal stability and surfactant aggregation can be investigated in detail, as can the thickness and refractive index of adsorbed layers. The theories of DLVO forces, polymer-induced forces (steric, bridging and depletion forces), and other types of forces can be tested experimentally. Two important aims are to investigate how details in the chemical composition of a surface can influence the surface forces, and to learn how the adsorption of surfactants and polymers modifies the surface interaction. For this we use, in addition to the various surface force techniques, a range of techniques for surface modification and surface characterisation. The division for surface chemistry is the host to one NUTEK competence centre “Surfactants based on Natural Products”, and one SSF program “Direct Digital Printing”. The surface chemistry division is also participating in the SSF programs “Colloid and Interface Technology” and “Nanochemistry” as well as the EU-project “Application of Amphiphilic Polymers to Structural and Pharmaceutical Research on Integral Membrane Proteins”. The research activities of the surface chemistry division are briefly described below.

ADVANCED UNDERGRADUATE TEACHING Technical Surface and Colloid Chemistry (3B1242, 4 credits)

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Surface Chemistry Graduate Teaching during 2000 Technical Surface and Colloid Chemistry (3B5204, 4 credits) Research seminars in Surface Chemistry, (3B5283, 4 credits) Project work in Surface Chemistry, (3B5214, 3 credits)

Registered Students

PRESENTATION OF RESEARCH ACTIVITIES STRUCTURE AND SYNERGISM OF SURFACTANT SYSTEMS Magnus Bergström Various systems containing surfactants are studied both theoretically and experimentally. The geometrical structure of aggregates formed in surfactant/surfactant (micelles and vesicles) as well as polyelectrolyte/surfactant mixtures are experimentally investigated mainly with small-angle neutron scattering (SANS) and small-angle x-ray scattering (SAXS). Measurements are performed among other places at Risø National Laboratory, Denmark and Institute Laue-Langevin, France. The micelles are in general shaped as tablets or ribbons, i.e. with a distinct thickness < width < length, but may be shaped as oblates or elongated rods or worms in special cases. The size and shape of spontaneously formed micelles and vesicles are evaluated from theories based on the aggregate curvature free energy from which the detailed aggregate geometry may be quantitatively calculated from e.g. the length of the surfactant tail, size and charge number of the head-group and asymmetry with respect to these quantities between two surfactants in a binary surfactant mixture. Synergistic effects in mixed surfactant systems, i.e. non-linear behaviour of the critical micelle concentration as a function of the surfactant composition, are studied. Several different cases are treated: mixtures of anionic and cationic surfactant, mixtures of an ionic and a nonionic surfactant, mixtures of two identically charged ionic surfactants with different cmcs. The synergistic effects are explained by a recently developed theory based on various entropic contributions to the aggregate free energy. The theoretical predictions are experimentally tested by the performance of surface tension measurements. Detailed models of adsorption processes at the interface between a charged as well as an uncharged hydrophobic material and water, and at the air/ water interface in mixed surfactant systems are developed in connection with atomic and surface force measurements. Quantities such as layer thickness and composition, surface tension etc can thus be obtained.

Luis Bastardo Katrin Boschkova Peter Hansen Abha Kapilashrami Mikael Kjellin Christian Kugge Atte Kumpulainen Lubica Macakova Marcus Persson Torbjörn Pettersson Mark Plunkett Evgeni Poptoshev Brita Rippner Sandra Rödner Therese Sennerfors Johan Stålgren Joakim Voltaire Monika Österberg

Visiting Scientists (> 1 month) Dr. Thomas Abraham, Edmonton, Canada Dr. Christel David, Thiasis, France

Figure 1. CMC for mixtures of two nonionic surfactants with rigid circular head groups of different size plotted against the mole fraction of Surfactant 1 in the aggregates. For all three curves the

10

Å2 and the sum of the cross-section areas of the two head groups to

9

a1hg + a2hg = 30 Å2. The difference in head group cross-section area

CMC / mM

area per aggregated surfactant was set to a constant value of a = 32

is ∆ahg ≡ a1hg - a2hg = 5 Å2 (solid line, approximately corresponding to β = -0.2), ∆ahg = 10 Å2 (dashed line, β = -0.8) and ∆ahg = 20 Å2 (dotted line, β = -2.2). The minimum of each curve is located at

8 7

compositions where the surfactant with the bulkiest head group is in excess. In mixtures of an ionic and a nonionic surfactant with different head group cross-section areas the two contributions to

6

synergistic effects always enhance one another and, hence, β values below -1 are obtained. Generally, the synergistic effects tend to increase with increasing asymmetry between the two surfactants.

5 0.0

0.2

0.4 0.6 Surfactant composition

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Surface Chemistry INTERFACIAL PROPERTIES OF BIOMOLECULES

Premises The laboratory for Chemical Surface Science (142 m2).

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Eva Blomberg In this research area we study interfacial properties of a wide range of biomolecules: from proteins to sugar-based surfactants. Previously we have focused on the mechanism of protein adsorption and the interaction between protein-coated surfaces by employing the interferometric surface force technique. With this technique it is possible to obtain information about the most important type of interactions for a protein system and on the structure of the adsorbed protein layer; it is also possible to determine if the protein undergoes large-scale conformational changes upon adsorption. This work was continued by investigations of the interactions between proteins and protein-rejecting surfaces and how the temperature influences the forces. We have also been studying the interfacial properties of complexes between hydrophobically modified polyelectrolytes, so called amphipols, and proteins. This is an important area since it has been shown that the amphipols can be used instead of surfactants to remove proteins from membranes and keep them in aqueous solution. Understanding the behaviour of amphipols adsorbed to hydrophobic surfaces is an essential step towards devising molecules, and conditions for using those, that will lead to preparations of membrane protein/amphipol complexes suitable for NMR and crystallisation studies. Surface force measurements on macroscopic samples are invaluable to obtain a detailed description of the thickness of the layer and the magnitude of repulsive and/or attractive forces when two amphipol-covered surfaces are brought closer together, as will often be the case in membrane protein crystallisation. The main conclusion according the physical properties of amphipol layers adsorbed to macroscopic surfaces are the following: anionic amphipols readily adsorb to hydrophobic surfaces at low and high ionic strength. At low ionic strength (≤ 10 mM NaCl), they form a dense layer with some tails extending up to 4-5 nm into the solution; such amphipol-covered surfaces adhere to each other when brought into contact. At higher electrolyte concentration (100 mM NaCl), the extended tails collapse, yielding a compact layer ca. 1 nm thick. A strong repulsion does not develop before the layers come into steric contact, and no adhesion is observed when the surfaces are separated, suggesting that the non-polar chains on the amphipol become hidden within the collapsed layer. The research was carried out in the frame of an EU-Biotechnology project, with research groups from France and Germany. Sugar based surfactants are less efficient in generating short-range repulsive forces than alkyl ethoxylates. This is a drawback in cleaning and dispersion applications. In this research area we will use alkylthiols with chemically grafted sugar groups in order to elucidate the mechanism of the shortrange attraction which is present between sugar based surfactants. For this purpose we will use glass surfaces coated with a thin layer of gold that has been further modified by functionalised alkylthiols. Two different alkylthiols with grafted sugar groups have been studied so far and their interfacial properties have been compared with those of an alkylthiol carrying a grafted ethylene oxide chain (6 ethylene oxide units). In conclusion, the force acting between surfaces coated with sugar functionalised alkylthiols with and without an ethylene oxide spacer is very similar at large surface separations. Moreover, on separation an attractive minimum in the force profile is observed and the attraction measured at short contact times can be explained by van der Waals forces (Figure 1). When the surfaces are left in contact for a longer time an increase in the attraction is observed, which is likely due to an extra contribution to the attraction from hydrogen bonding between the sugar groups. This means that the chemically grafted sugar

Surface Chemistry groups need time (seconds) to find the most favourable configuration in order to form hydrogen bonds with the sugar groups on the second surfaces. Finally, the steep short-range repulsion is of a larger range between sugar thiols with an ethylene oxide spacer compared to sugar thiols without the spacer and this is related to the larger size and flexibility of the latter head-group. The forces between surfaces coated with E6-thiols are, unlike for the sugar functionalised thiols, purely repulsive. This indicates that the van der Waals force is small between these layers and that the ethylene oxide groups, as expected, are unable to form hydrogen bonds with each other. This research will be continued in collaboration with Prof. Bo Liedberg and Docent Peter Konradsson at Linköping University within the Competence centre for Surfactants based on Natural Products. 0.1

Figure 2. The adhesion force as a function of the time the surfaces were in contact. Filled and unfilled symbols correspond to surfaces coated with

0.09 0.08

Glob-O-thiol and Glob-E-thiol, respectively. The solid line is included as a guide for the eyes.

0.07 0.06 0.05

During last year a study concerning fluoro-surfactants 0.04 has been initiated. Earlier studies have shown that wall 0.03 interactions of proteins in capillary electrophoresis can be 0.02 avoided by using fluoro-surfactants as additives. Initially, 0.01 we will study the build-up of a cationic fluorosurfactant 0 10 0 layer on mica using the surface force technique. Some studies of interfacial properties of dendrons have also been initiated in collaboration with Prof. Anders Hult. These collaborative efforts are carried out within the framework of the SSF program Nanochemistry (co-ordinator Prof. Johan Roeraade, KTH) and the SSF program Colloid and Interface Technology (co-ordinator Prof. Björn Lindman, Lund).

20

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Contact time (s)

FUNDAMENTAL STUDIES OF SURFACE INTERACTIONS AND ADSORPTION Per Claesson During the past year the main emphasis has been put into three different areas: studies of interfacial and bulk properties of polyelectrolytes and polyelectrolyte-surfactant mixtures, interactions between gold surfaces modified by functionalised alkylthiols and interfacial properties of surfactants. Adsorption of polyelectrolytes and polyelectrolyte-surfactant mixtures and the interactions between surfaces coated with such adsorbed layers were studied using a range of methods. For instance, surface force instruments, atomic force microscopy imaging, adsorption studies using ESCA and quartz crystal microbalance, light scattering, neutron scattering and small angle X-ray scattering. The small angle X-ray scattering technique has not previously been used in out division. However, it proved very useful for determining the structure of polyelectrolyte-surfactant complexes. Both hexagonal and lamellar phases were found. The effect of various polyelectrolytes on interactions between cellulose surfaces was thoroughly investigated and of central importance for two theses presented during 2000: Monika Österbergs PhD-thesis entitled “On the interactions in cellulose systems: Surface forces and adsorption” and Evgeni Poptoshevs licentiate thesis “Surface interactions related to papermaking systems”. Polyelectrolytes are common additives in the papermaking industry and during textile washing where they have a multitude of functions, e.g. as retention agents, wet- and dry strength additives and binders of compounds to cloths. It is no simple matter to quantitatively

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Surface Chemistry

Adsorbed amount, mg/m^2

determine the adsorbed amount of polyelectrolytes on macroscopic cellulose surfaces. Results from the common ellipsometry and reflectometry techniques as well as the QCM-D devices are difficult to interpret due to swelling of the surface layer. For this reason we used another approach and Main Equipments Interferometric surface force apparatus analysed the adsorbed amount of polyelectrolytes on cellulose using ESCA. Mark II A simple way of estimating the adsorbed amount by ESCA is to determine the atomic percent of the different atoms. In our case the nitrogen signal Interferometric surface force apparatus arises from adsorbed polyelectrolytes whereas no such signal emanates from Mark IV the cellulose substrate. However, with a bit more effort one can go one step further and determine the adsorbed amount quantitatively and report the Tribological surface force apparatus values in e.g. mg/m2. The fist step in the quantification procedure is to MASIF surface force apparatus determine the adsorbed amount on mica, where it easily can be quantified by means of ESCA by comparing the signal from potassium (in the mica AFM (access to) crystal) and from nitrogen (from the polyelectrolyte). Since the crystal structure of mica is well known the ratio of the potassium and nitrogen ESCA (access to) signal can be used for a quantitative determination of the adsorbed amount. Quartz crystal microbalance-Dissipation The results from mica are then utilised to make a calibration curve giving (Q-sense) the adsorbed amount of polyelectrolyte as a function of the nitrogen signal intensity. This signal from the polyelectrolyte is in the next step measured Langmuir Blodgett instrument on cellulose surfaces and the adsorbed amount determined from the calibration curve. One example of the results obtained is shown in Figure 2. Evaporation unit The adsorbed amount of polyelectrolyte decreases with the charge denTensiometer-Wetting device sity of the polyelectrolyte. However, the number of charges from the polyelectrolyte that is adsorbed to the cellulose surface is highest for the most Thin Film Balance highly charged polyelectrolyte. This shows that the number of adsorbed polyelectrolyte charges in general is not equal to the number of charged sites Sum Frequency Generation spectrometer on the cellulose surface. During the past years we have also put a large emphasis on developing modified gold surfaces that are suitable for surface force studies, i.e. the surfaces should be molecularly smooth over sufficiently large surface areas. This was achieved in collaboration with Prof. Liedberg in Linköping and culminated with the PhD-thesis “Novel Surfaces for Force Measurements” presented by Thomas Ederth late 1999. In particular, a range of smooth gold surfaces modified by ω−functionalised alkylthiols was prepared and used for surface force and wetting measurements. The rationale for the large emphasis put on thiolated gold is that the stability of the monomolecular coating is superb, the preparation technique, once a smooth gold surface has been obtained, is simple, and the surface chemistry can be varied and controlled to give a wide range of surface properties. The self-assembled monolayers (SAMs) on gold surfaces obtained using simple long-chained Figure 3. The adsorbed amount of cationic alkylthiols have a very high packing density, with the hydrocarbon chains in polyelectrolyte on cellulose films in the plateau crystalline order. Even though a SAM forms very rapidly on the substrate, it region as a function of the polyelectrolyte is necessary to use adsorption times of 15 h or more to obtain well-ordered, charge density. defect-free SAMs. The work up to date has mainly been focused on formally uncharged surfaces with a 0,5 controlled wettability. This was achieved by using 0,4 mixtures of methyl- and hydroxy-terminated alkylthiols. 0,3 From these studies we have been able to conclude that the wettability of these stable and crystalline 0,2 coatings determine whether or not an attraction in 0,1 excess of the van der Waals force is observed. When the contact angle is below 90° the attractive force is 0,0 well described by the Lifshitz theory for van der 0 1 0 2 0 3 0 4 0 5 0 6 0 7 0 8 0 9 0 100 Waals forces. However, for higher water contact anPolyelectrolyte Charge Density, % gles a considerably more long-range attraction is ob-

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Surface Chemistry served. From the shape of the force curve, which starts with a sudden attractive step, we could conclude that bridging sub-microscopic bubbles cause the attraction. This conclusion is valid both then the wetting is controlled by the surface chemistry and then it is determined by changing the solvent composition. We have now just entered the next stage of the research where the thiol modified surfaces will be used for a range of studies with the aim of understanding the effect of the surface chemical composition on adsorption, wetting and surface forces. The PhD-students Johan Stålgren and Atte Kumpulainen will largely carry out this work. A systematic study of the structure-function behaviour of a range of sugar based and other non-ionic surfactants is being undertaken by two PhDstudent, Mikael Kjellin and Marcus Persson working within the competence centre “Surfactants Based on Natural Products”. Surface force measurements between surfactant layers adsorbed at solid -liquid, or air-liquid, interfaces give important clues to their end-applicability, particularly their ability to stabilise or destabilise foams, emulsions and dispersions. Wetting, equilibrium and dynamic surface tension measurements are also applied to the studies. Fluorescence measurements and small angle neutron scattering experiments give important information on the associative structures formed in bulk solution. This research effort will continue also during the coming year.

DYNAMIC SURFACE FORCES AND CELLULOSE INTERACTIONS Mark Rutland The most exciting development in this area is acquisition of Sum Frequency Generation (SFG) Spectroscopy equipment to the department. The SFG lab is a joint facility shared by Corrosion Science, Surface Chemistry and Materials Physics and is housed on the floor above the existing Surface Forces Laboratory. It was funded by a TFR large equipment grant and the equipment is already functioning satisfactorily. A postgraduate student will be commencing in this area in February 2001, funded by the SSF Graduate School for Colloid and Interfacial Technology. The technique employs a non-linear optical phenomenon which is detectable only with intense laser light and which usually occurs only at surfaces for reasons of symmetry. This allows molecular spectroscopy of the surface layer to be performed since the technique is surface specific. Not only can the nature of the surface adsorbed molecules be detected, but their conformation can also be determined. Combined with the rapid data acquisition this means that dynamic processes at surfaces can also be studied. Through monitoring the surface conformation of monolayer films under shear, we intend to investigate the mechanisms of friction at the molecular level, as well as having a powerful new tool for investigating a whole range of problems in surface and colloid science. Friction of cellulose surfaces is also being studied for its relevance to papermaking systems. This project is a collaboration with Fredrik Tiberg and Goran Bogdanovic at the Institute for Surface Chemistry. We are making progress, not only in understanding friction for cellulosic systems, but also friction at the molecular level. During 2000 we expanded our successful contact mechanical treatment of cellulose friction in air to investigations in liquid. We have shown that when cellulose interacts laterally with another substrate in air, the frictional force is not linear with the applied load but rather with the true area of contact. The shear strength is clearly dependent on the adhesion hysteresis, an important mechanistic finding, and when hydrogen bonds are possible, the frictional forces increase dramatically. In water however, an entirely different behaviour is observed. The frictional load dependence is close to linear and no adhesion is seen. Over the pH range 3 to 9 where double layer repulsion of the surfaces goes from negligible to very significant, the frictional behaviour is basi-

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Surface Chemistry cally unchanged. This indicates that in this particular case the solution surface chemistry has little or no effect on the frictional force, friction is due to contact of nanoscopic asperities (which do not flatten since there is no adhesive load in this case) and the nature of the contact of these asperities is independent of the pH. Other work involving cellulose is the use of Langmuir Blodgett films of cellulose for measuring interactions with model fillers using the MASIF surface force apparatus. This technique has been used to study how cationically modified polyelectrolytes, used as wet strength additives by the paper industry, behave at relevant surfaces. We have studied the effect of molecular weight and charge density on the adsorption, charging and bridging forces between surfaces. Dynamic Surface Forces are not limited to friction. We are actively studying how the adhesion of two viscoelastic polymer layers behaves dynamically. To do this, we control the polymers viscoelasticity via the solvent quality of the medium. (This also has a marked effect on the normal forces). Depending on our solvent conditions (and therefore on the strength of the polymer-polymer interaction) we obtain various dynamic adhesion regimes. In some cases the adhesion is dependent on the time the surfaces spend in contact, in other cases this parameter is not important and the rate at which the surfaces are separated is important! We have shown that the former case is due to interdiffusion of polymers leading to enhanced adhesion whereas we believe that latter case is related to the rate of “crack propagation” as the surfaces separate.

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Low Maximum load regime

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Figure 4. Pull-off force as a function of contact time for polymer

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coated surfaces in poor solvent. Note log scale for contact time.

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High Maximum load regime

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The data in black is for a low maximum load, whilst the data in grey is for the high maximum load regime. The lines are logarithmic fits to the data. The fact that the data is linear on

1

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contact time (s)

100

this scale is strong evidence that the increasing adhesion with time is due to polymer interdiffusion.

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Theoretical Chemistry Theoretical Chemistry is a scientific activity in which one seeks to obtain unifying theoretical concepts and models to describe properties of matter and which can be used to predict and interpret data obtained in experimental contexts. Modern theoretical chemistry is closely related to the concept of simulations, and to the validation of models through simulations. Apart from model validation, simulations are used to interpret and predict data and processes. Since mid-1999 Theoretical Chemistry defines a new discipline at KTH, and forms a new division there.

Staff Professors Hans Ågren Faris Gel’mukhanov

Senior Researchers Yi Luo Boris F. Minaev Olav Vahtras Bernd Schimmelpfennig Chuan Kui Wang

The general definition given above covers a broad range of systems and fields in research. At KTH we take account of the fact that “molecular” materials are recognized as the materials of the future because their molecular nature combined with the versatility of synthetic chemistry can be exploited to optimize electromagnetic properties of various devices. In collaboration with others at KTH and elsewhere, the theoretical simulations can be linked to both the production and the characterization of the materials. “Molecular” is understood in a broad sense, including isolated molecules as well as molecules in crystalline-, polymeric-, dissolved-, interfacedand surface adsorbed forms. We are engaged in method development, in program coding and in simulations using these codes. We take interest in both basic and applied aspects, and in experimentaltheoretical collaboration.

Group Survey Networks Coordinator of the EU TMR project: “Molecular Properties and Molecular Materials” 9 nodes. Participator of the SSF (Stiftelsen för Strategisk Forskning) network: “Center for Advanced Molecular Materials (CAMM)”. 5 nodes. Participator of the FOA/FMVnetwork on Photonics: “Materials and Components for Laser Protection”. (5 nodes) Participator of the EU TMR project “Hard carbon nitride based materials” (8 nodes) Participator of the EU COST/D9 project “Molecules in mixed condensed phase media” (6 nodes) Coordinator of the EU INTAS project “Theory and application of spin catalysis” (7 nodes) Participator of the EU COST/D9 project “Core excitation and electron attachment in extended systems”. (6 nodes) Participator in the “Centre of Excellence for New Functional Materials Design and Diagnostics (ESTOMATERIALS)”, 6 nodes.

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Theoretical Chemistry Funding

Phd Students Olexandre Plashkevych (PhD May 2000) Maria Engström Pawel Salek Peter Cronstrand Peter Macak Timofei Privalov Alexandre Baev Bransolav Jansik Alexander Loboda Jing-Dong Guo Oscar Rubio

Apart from the networks given above, the projects have been supported through different channels, by external university contributions (Linköping, Stockholm, Uppsala universities), by the Swedish national research council, the Royal Academy of science (KVA), the Swedish institute (SI), and by STINT.

ADVANCED UNDERGRADUATE COURSES Optical Process and Properties, 5 points - 3B1655 Molecular modelling on a Computer, 5 points - 3B1650

Masters Course and Projects Masters Course in Computational Chemistry - 3B5640 Masters Projects - 3B1016 (www.theochem.kth.se/masters-projects/)

PhD courses Optical Process with Applications in Photonics and Biophotonics, 5 points - 3A5701 Molecular Properties and Molecular Materials, 5 points - 3A5702 X-ray spectroscopies in Natural Sciences, 6 points - 3A5703 Molecular Orbital Theory, 5 points - 3A5704 Quantum Chemistry and the Chemical Bond, 5 points - 3A5705 Molecular Modelling on a Computer, 10 points - 3A5706

Research The research focuses on reactions, properties and spectra covering a large part of the electromagnetic wavelength region; X-ray, optical and microwave regions relevant for the three main research areas listed below; Molecular Photonics and Electronics Response Theory Solvent modelling Multi-photon absorption NLO in liquids, polymers and fullerenese Molecular Wires Spin Chemistry, Molecular Magnetism and Relativity Spin catalysis and spin uncoupling phenomena Molecular magnetism, NMR and ESR parameters Relativistic quantum chemistry X-ray Chemistry and Physics X-ray Raman scattering Near-edge X-ray absorption Non-resonant spectroscopies

DESCRIPTION OF RESEARCH FIELDS MOLECULAR PHOTONICS AND ELECTRONICS Non-linear optical response Response theory has formed the backbone of our simulation work. It describes how a property is changed in the presence of a perturbing field. This field may be external or internal to the molecular system, it can be electric or magnetic, time-dependent or time-independent. The coding effort is collected in the DALTON program system, which is the result of a broad Scandinavian collaboration. It can be seen as a general 4:th order

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Theoretical Chemistry toolbox for quantum chemical property and spectral calculations. The effort of the KTH group has, concerning the coding, basically been focused on higher order (quadratic and cubic) response functions, on computational implementations for extended species, on spin-orbit and vibronic coupling and hyperfine coupling parameters, on solvent reaction field response and on approximate relativistic models for response properties.

Solvent Modelling In most experiments and for most situations where NLO or other properties are used technically, there is a medium which surrounds the active site or molecule. The effect of having such a medium is two-fold; it modifies the property of the single solute molecule (or system of molecules); and it modifies the external Maxwell field to a local counterpart. We have addressed these medium effects by developing reaction field response theory in which the response equations of a given order is solved in the presence of a reaction field. We have also for this purpose worked out simplifying models, like the so-called semiclassical models. Schematic picture of four type of solvent models developed and used by the theoretical chemistry group.

Multi-photon absorption Our interest in this field is to find out how multi-photon spectra are formed in real and idealized systems, how the special selection rules and polarization dependences can be used to study the organization of excited states and to assign such states. Concerning the applicative aspects we focus on how multi-photon absorption and excited state absorption can be used for optical limiting, that is to theoretically predict materials with large two-photon and excited-state absorption to protect human eyes and devices from intense laser light. Special attention is then paid to the understanding of the role of vibrational contributions, of the conjugation length and dimensionality of charge-transfer networks and of the polarity of solutions.

Nonlinear absorption Two−photon absorption

Optical limiting I out

ω ω

Schematic picture of two-photon absorption and optical limiting. The lower panel

I in

shows multi-branched systems which are predicted to have good characteristics

CH3

with respet to optical limiting.

N N

NLO in liquids, polymers and fullerenes Our first efforts on NLO focused on basic aspects like wave function parametrizations, vibrational effects and dispersion relations. We have proceeded with successively larger systems with the goal to match molecular materials used in real applications. This has been accomplished through modelling of environmental (solvent) effects, through the development of computational-saving algorithms and parallelization. We have thereby reached the so-called Hartree-Fock limit for up to fourth order NLO properties for the fullerenes; the NLO convergence lengths in oligomers; and obtained properties of unpolar liquids with basically the same precision as for the gas phase. Present projects focus on NLO in molecular crystals and 3D networks, on polar solvents through molecular dynamics simulations, and on the inclusion of relativistic effects. We have also worked on a module for non-linear response

N

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Theoretical Chemistry based on so-called time-dependent DFT (density functional theory). Diagrams showing computed polarizability (a) and second order hyperpolarizability (g) for polyenes in vacuum and in solvent.

Molecular electronics Molecular electronics has attracted much attention owing to the possibility to design individual molecules that can function identically or analogously to transistors, diodes, conductors and other key components of today’s microcircuits. Parallel to the extensive experimental work, theoretical research activity has now become an important factor in the development of such molecular devices. In recent years, formal theories to describe electron transport processes in molecular devices have been developed by several groups. A big challenge for theoretical simulations is to describe the current-voltage (I-V) characteristica of molecular devices, which have been directly measured by experiment. During the year 2000 we developed a general approach to characterize the electron transport process in molecular devices using elastic-scattering Green’s function theory. We introduced the frontier molecular orbital theory to describe the surface-molecule coupling and used hybrid density-functional theory to compute the geometrical and electronic structures. Our calculated I-V curves for some molecular wires between gold electrodes show very good agreement with experiment and infers optimism for further work in this field. Current and conductance of a benzene-1,4-dithiol molecule connected to gold surfaces at room temperature of $T=300$ K from (a) experiment of Reed et al., Science, 278, (1997) 25 (b) previous calculation (Phys. Rev. Lett., 84,(200)979), and (c) present Green’s function and frontier orbital method.

SPIN CHEMISTRY, MOLECULAR MAGNETISM AND RELATIVITY In this area we take interest in computing spin dependent parameters, like EPR and NMR parameters, and to study the role of the “electron spin” for material properties and catalytic processes.

Spin catalysis and spin uncoupling The “spin-catalysis” concept is based on the crucial role of electron spin in the control of the reaction channels in the region of activated complexes. It can be paramagnetically induced or spin-orbit coupling induced. The spin uncoupling shows how reactants prepare for a reaction. “Spin catalysis” and “spin uncoupling” have served as basic concepts in a number of investigations of catalytic phenomena in our group. As an example; we have obtained new thumb rules for surface hydrocarbon adsorbate reactions using the spin uncoupling concept. We have also taken interest in the role “spin” or rather the breaking of spin selection in Spin-orbit coupling effect in photodecomposition of furan into cyclopropenyl ketone.

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Theoretical Chemistry atmospheric absorption and emission transitions, in particular so for the phosphorescence phenomenon. Spin-orbit coupling induced catalysis of epoxidation of olefins using Manganese-(salen) as catalysor.

Simulations of spin-markers through EPR/NMR parameters In this project we take account of the fact the magnetic resonance spectroscopies have proven very useful in chemical and biochemical research. EPR and NMR spectra are commonly interpreted from simulations, where experimental results are matched with parameters in the theoretical expressions. For example, many biological processes are mediated by radicals for which there is great need for reliable calculations of the so-called g-tensors that “mark” such radicals. The g-tensor is a parameter in the spin Hamiltonian which describes the interactions between the electron spin and external magnetic fields. We have proposed and applied analytic response theory methods to compute hyperfine interaction parameters like these EPR g-tensors, and also NMR spinspin coupling constants. The simulation of spin markers of E. coli RNR serves as an example. On the basis of simulations using our g-tensor code we could suggest a role of hydrogen bonding to the tyrosyl radical in ribonucleotide reductase.

Trp48

Asp237 His118

Catalytic site of E. coli of RNR. The tyrosyl radical (Tyr122) is

Glu115

stabilized and maintained within the protein framework by a diferric oxygen center.

Relativistic effects in heavy-element compounds

Fe Tyr122

Glu238

O Fe

Asp84 Glu204

Relativistic effects become more and more important the heavier the element. We look at this problem at several levels of complication, but have mostly used a Douglas-Kroll-Hess approach to reduce the four-component Dirac equation to a oneor two-component scheme. Several projects are presently running, to mention; investigations of actinide compounds, calculation of relativistic effects in NMR/EPR for heavy element; inclusion of atomic spin-orbit mean-field and Douglas-KrollHess approaches in a response theory framework. Some results in these projects have already been obtained. Relativistic calculations of the D3 structure of Th4+ with 9 water molecules in the first coordination shell.

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Theoretical Chemistry X-RAY CHEMISTRY AND PHYSICS X-RAY RAMAN SCATTERING

A.A f

γ

f

γ

γ

c γ o Resonant scattering II

o Thomson scattering I

X-ray spectroscopy is an old scientific branch which has been greatly revitalized by the introduction of modern synchrotron radiation sources and by the possibilities of (still future) free electron lasers. The element-selectivity of X-ray methods probes local electronic and geometric structures of molecules and solids. We have developed and applied theory for resonant X-ray scattering and its application in chemistry and physics. The dynamical aspects of the X-ray scattering process have then been of central interest. We have shown that frequency detuK.A ning allows to change the duration of the scattering process and thereby to distinguish molecular processes f with different time scales. The temporal theory with a wave packet formalism has allowed us to predict a set of γ γ new effects, to name a few; “symmetry restoration”, “vic brational collapse”, “control of dissociation”, “the spectral hole”, and “Doppler effects” on ejected Auger electrons. Several projects are presently running with both molecular and solid-state applications. o Diagrams corresponding to each of the three terms of the KramersHeisenberg formula for resonant X-ray scattering. The time arrow is directed upwards.

Near-edge X-ray absorption

C60 Calculated NEXAFS spectra

NEXAFS and EXAFS (near- and extended edge X-ray absorption fine structure) spectroscopies are potentially very useful for diagnostics of samples. In the case of NEXAFS we have taken interest in property-to-structure relationships like “building block principle”, “matrix quenching”, “bondlength-with-the-ruler” and “orientational probing”. We have developed simulation methods to address these features in the X-ray edge spectra; both in the so-called ab initio and density functional theory frameworks. These have been used to study electronic and geometric structures of species as different as small molecules, amino acids, polymers and surface adsorbates. In the case of EXAFS we have derived a new principle that allows complete structural information (bond lengths and bond angles) also for randomly oriented and amorphous samples (“EXAFS in the Raman mode”).

fwhm=0.5 eV

Experiment

Full core hole

Intensity (Mb)

Nonresonant scattering III

Z+1

Transition potential

Ground state

Computations of the discrete NEXAFS spectrum of C60 below ionization potential at 290 eV using 0 282

284

286

288

290

292

294

296

298

300

different models.

Photon energy (eV)

Non-resonant spectroscopies

DFT−TP

Owing to the development of synchrotron facilities much of the emphasis has been moved to the resonant counterparts of the core electron spectroscopies. Even so the non-resonant spectroscopies have taken advantage of this development as well. Fine vibronic structure, precise settings of chemical shifts and improved intensity modelling are topics which we have worked on. Computations of the outer ionization potentials of ferrocene using our derived transition potential DFT method, compared to results from conventional methods.

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Publications Analytical Chemistry

Inorganic Chemistry

Publications E.Furusjö and L.G.Danielsson Target Testing Procedures for Chemical Kinetics from Spectroscopic Data with Absorption Shiftsd and Baseline Drift. Chemometrics and Intelligent Laboratory Systems, 50(1) 2000, 63

New Class of Oligonuclear Platinum-Thallium Compounds with a Direct Metal-Metal Bond. 4. Tl-Pt(CN)5 in the Solid State - a Multi-Method Study of an Unusual Compound Containing Inorganic Wires Jalilehvand, F., Eriksson, L., Glaser, J., Maliarik, M., Mink, J., Sandström, M., Tóth, T., Tóth, J. Chem. Eur. J. In press.

L. G Danielsson and X.Yang Transport of Low Molecular Weight Anions Through a Nafion Ionomer Membrane: Applications to Kraft Cooking Liquors Analytical Chemistry 72(7) 2000, 1564

Cyanide Exchange on Tl(CN)4¯ in Aqueous Solution Studied by 205Tl and 13C NMR Bányai, I. , Glaser, J, Tóth, I. Eur. J. Inorg. Chem. In press.

O. Berntsson, L. G. Danielsson, M.O.Johansson and S. Folestad Quantitative Determination of Content in Binary Powder Mixtures using Diffuse Reflectance Near Infrared Spectrometry and Multivariate Analysis Analytica Chimica Acta, 419, 2000, 45

E. Furusjö and L. G. Danielsson Uncertainty in Rate Constants Estimated from Spectral Data With Baseline Drift Journal of Chemometrics 14 (2000) 483 D. Templeton, F.Ariese, R. Cornelis, L.G.Danielsson, H.Muntau and H van Leeuwen IUPAC guidelines for Terms related to Chemical Speciation and Fractionation Of Trace Elements: Definitions, Structural Aspects and Methodological Approaches Pure and Applied Chemistry 72(8), 2000 E. Litborn, M. Curcio, Å.Emmer and J. Roeraade Synthesis and Analysis of Chemical Components in Nanoscale Proc. Micro TAS 2000, A. Van den Berg (ed). Page 447-453, Kluwer, Dordrecht, The Netherlands A. Hanning, J Westberg and J. Roeraade A Liquid Core Waveguide Fluorescence Detector for Multicapillary Electrophoresis, Applied to DNA Sequencing in a 91 Capillary Array Electrophoresis 21 (2000) 3290

2, 2' - Bipyridinium Diperchlorate, [C10N2H102+](ClO4-)2 Ma, G.-B., Ilyukhin, A., Glaser, J. Acta Crystallogr. C. 2000, C56, 1473-1475. . Small Platinum-Thallium Clusters Stabilised by Ethylenediamine, Pt(CN)5Tl(en)n-1 (n=1-3). Characterisation in Solution by Multinuclear NMR and in Solid by X-ray Diffraction. Ma, G.-B., Kritikos, M., Glaser, J. Eur. J. Inorg. Chem. In press. The Rates and Mechanisms of Water exchange of UO22+(aq) and UO2(oxalate)F(H2O)2-: A Variable Temperature 17O and 19F NMR Study I. Farkas, I. Bányai, Z. Szabó, U. Wahlgren and I. Grenthe Inorg. Chem., 2000, 39, 799805 The Solution Thermolysis Approach to Molybdenum(V) Alkoxides: Synthesis, Solid State and Solution Structures of the Bimetallic Alkoxides of Molybdenum(V) and Niobium(V), Tantalum(V) and Tungsten(VI). A. Johansson, M. Roman, G. A. Seisenbaeva, L. Kloo, Z. Szabó and V. G. Kessler. J. Chem. Soc. Dalton Trans. 2000, 387-394 19F NMR Study of Equilibria and Dynamics of the Al3+ - F- System. A. Bodor, I. Tóth, I. Bányai, Z. Szabó and G. T. Hefter. Inorg. Chem., 2000, 39, 2530-2537 Structure and Dynamics in the Complex-ion (UO2)2(CO3)(OH)3Z. Szabó, H. Moll and I. Grenthe. J. Chem. Soc. Dalton Trans. 2000, 3158-3161

E. Litborn and J. Roeraade Liquid Lid for Biochemical Reactions in ChipBased Nanovials J. Chromatogr B-754 (2000) 137

The Hydrolysis of Dioxouranium(VI) Investigated Using EXAFS and 17O NMR. H. Moll, T. Reich and Z. Szabó , Radiochim. Acta 88. 411-415 (2000)

E. Litborn, Å. Emmer and J. Roeraade Parallel Reactions in Open Chip-Based Nanovials with Continuous Compensations for Solvent Evaporation Electrophoresis 21 (2000) 91

Potentiometric and Multinuclear NMR Study of the Binary and Ternary Uranium(VI)-LFluoride Systems, Where L Is _Hydroxycarboxylate or Glycine Z. Szabó and I. Grenthe, Inorg. Chem., 2000, 39, 5036-5043

A. Hanning, P. Lindberg, J. Westberg and J. Roeraade Laser-Induced Fluorescence Detection by Liquid Core Waveguiding Applied to DNA Sequencing by Capillary Electrophoresis Analytical Chemistry 72 (2000) 3423

Solution Coordination Chemistry of Uranium in the Binary UO22+-SO42- and the Ternary - UO22+-SO42—OH- System. H. Moll, T. Reich, C. Hennig, A. Rossberg, Z. Szabó and I. Grenthe, Radiochim. Acta 88. 559-566 (2000)

P.Lindberg and J. Roeraade DNA Dequencing at Elevated Temperature by Capillary Electrophoresis In: Methods in Molecular Biology, Vol. 163 Capillary Electrophoresis Of Nucleic Acids, Vol 2. Humana Press Inc, Totoway, NJ, in press Å. Emmer and J. Roeraade Wall Deactivation woth Fluorosurfactants for Capillary Electrophoretic Analysis of Biomolecules J. Chromatogr. In press J. Roeraade From Crushed Bricks to Microchips In: A Century of Separation Science, J.Issac (ed), Marcel Dekker Inc New York (in press)

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Time-Resolved Laser-Induced Fluorescence of Uranium(VI) Hydroxo-Complexes at Different temperatures V. Eliet, I. Grenthe G. and Bidoglio, Applied Spectroscopy 54. 99-105 (2000) A Theoretical Study of the structure of tricarbonatodioxouranate L. Gagliardi, I. Grenthe and B. O. Roos, Inorg. Chem. In print. “Investigation of the Polyiodides H3O.Ix (x = 3, 5 or 7) as Dibenzo-18-crown-6 Complexes”, L. Kloo, P.H. Svensson and M.J. Taylor, J. Chem. Soc., Dalton Trans. (2000), 1061-5.

“Ab Initio Spectroscopic Properties of HgTl+”, R. Wesendrup, L. Kloo and P. Schwerdtfeger, Int. J. Mass Spectrosc., 201 (2000) 17-21. “The Solution Structure of Ribosomal Protein L36 from Thermus Thermophilus Reveals a Novel Type of Zinc Finger”, T Härd, A. Rak, P. Allard, L. Kloo and M. Garber, J. Molec. Biol., 296 (2000) 169-80. “Metal Iodides in Polyiodide Networks - The Structural Chemistry of Complex Thallium Iodides with Excess of Iodine”, P.H. Svensson, G. Raud and L. Kloo, Eur. J. Inorg. Chem. (2000) 1275-82. “Raman Investigation of Indium Complexes: Evidence of the In2I7- Ion” M.J. Taylor and L.A. Kloo, J. Raman Spectrosc., 31 (2000) 465-8. “On the Intermolecular Bonding in Polyiodides”, P.H. Svensson, L. Kloo and J. Rosdahl, Accepted for publication in Eur.J.Inorg.Chem. “Monocations of Bismuth and Indium in Arene Media: A Spectroscopic and EXAFS Investigation”, A.N. Kuznetsov, B.A. Popovkin, M.J. Taylor, W.H. Henderson and L. Bengtsson-Kloo, J. Chem. Soc., Dalton Trans. (2000) 1777-81. “Ab Initio Calculations on Bismuth Cluster Cations”, A.N. Kuznetsov, M. Lindsjö, J. Rosdahl, L. Kloo, Chemistry Eur. J., in press. “The Solution Thermolysis Approach to Molybdenum(V) Alkoxides: Synthesis, Solid State and Solution Structures of the Bimetallic Alkoxides of Molybdenum(V) and Niobium(V), Tantalum(V) and Tungsten(VI)”, Johansson, M. Roman, G.A. Seisenbaeva, L. Kloo, Z. Szabo and V. Kessler, J. Chem. Soc., Dalton Trans., (2000) 387-94. Crystal and Liquid Structure of N,Ndimethylthioformamide and N,Ndimethylformamide, Borrmann, H., Persson, I., Sandström, M. and Stålhandske, C.M.V. J. Chem. Soc., Perkin Trans. 2, (2000) 393402. Hydration of the Yttrium Ions in Aqueous Solution. An X-ray Diffraction and XAFS Structural Study. Lindquist-Reis, P., Lamble, K., Pattanaik, S., Persson, I., and Sandström, M. J. Phys. Chem. B 104 (2000) 402-408. Structure of the solvated yttrium(III) ion in the oxygen donor solvents dimethyl sulfoxide, Lindqvist-Reis, P., Näslund, J., Persson, I, Sandström, M. N,N-dimethylformamide and N,N´-dimethylpropyleneurea and crystal structures of [Y(dmso)]8I3 and [Y(dmpu)]6I3. J. Chem. Soc., Dalton Trans. (2000) 2703-2710. Steric Effects Control the Structure of the Solvated Lanthanum(III) Ion in Aqueous, Dimethyl Sulfoxide and N, N´Dimethylpropyleneurea Solution. An EXAFS and Large Angle X-Ray Scattering Study, Näslund, J., Lindqvist-Reis, P., Persson, I, Sandström, M. Inorg. Chem. 39 (2000) 40064011. Solvation of the Bismuth(III) Ion by Water, Dimethylsulfoxide, N,N´-Dimethylpropylene Urea, and N,N-Dimethylthioformamide. An EXAFS, Large Angle X-Ray Scattering and Crystallographic Study, Näslund, J., Persson, I. and Sandström, M. Inorg. Chem. 39 (2000) 4012-4021. Model Extended X-ray Absorption Fine Structure (EXAFS) Spectra from Molecular Dynamics Data for Ca2+ and Al3+ Aqueous Solutions, Spångberg, D., Hermansson, K., Lindqvist-Reis, P., Jalilehvand, F., Sandström, M. and Persson, I. J. Phys. Chem. B 104 (2000) 10467-10472.

Hydration of the Calcium Ion. An EXAFS, Large Angle X-Ray Scattering and Molecular Dynamics Simulation Study, Jalilehvand, F., Spångberg, D., Lindqvist-Reis, P., Hermansson, K., Persson, I., and Sandström, M. J. Am. Chem. Soc. 123 (2001) 431-444. New Class of Oligonuclear Platinum-Thallium Compounds with a Direct Metal-Metal Bond. 4. Tl-Pt(CN)5 in the Solid State - a Multi-Method Study of an Unusual Compound Containing Inorganic Wires. Jalilehvand, F.,Eriksson, L., Glaser, J., Maliarik, M., Mink, J., Sandström, M., Tóth, I. and Tóth, J. Chemistry, a European Journal 2001, In the press. Hydration of some large and highly charged ions, M. Sandström, I. Persson, F. Jalilehvand, P. Lindquist-Reis, D. Spångberg and K. Hermansson, J. Synchrotron Radiation, 8 (2001), In the press.

Publications Nuclear Chemistry

Organic Chemistry

Publications

Publications

A.R. Cherkasov, V. Galkin, R. Cherkasov “Inductive” electronegativity scale: 2. ‘Inductive’ analog of chemical hardness Journal of Molecular Structure (Theochem) 497 (2000) 115-121

M. Drews, M. Doverskog, L. Öhman, B.E. Chapman, U. Jacobsson, P.W. Kuchel and L. Häggström, Pathways of glutamine metabolism in Spodoptera frugiperda (Sf9) insect cells: evidence for the presence of the nitrogen assimilation system, and a metabolic switch by 1 H/15N NMR. J. Biotechnol. 2000, 78, 23-37.

Artem Cherkasov and Mats Jonsson A New Method for Estimation of Homolytic C-H Bond Dissociation Enthalpies J. Chem. Inf. Comput. Sci. Vol. 40, No. 5, 2000 1222-1226. Daqing Cui and Tr ygve Eriksen Fracture-filling minerals as uranium sinks and sources, a natural analogue study at Palmutto, Finland. Radiochimica Acta 88, 751-755 (2000). J. Bruno, E. Cera, U-B Eklund, T. Eriksen, M. Grive and K. Spahiu Experimental determination and chemical modelling of radiolytic processes at the spent fuel/water interface.Radiochim. Acta, 88, 513-519 (2000) Goldstein S., Czapski G., Lind J. and Merényi G., Tyrosine Nitration by Simultaneous Generation of .NO and O2.under Physiological Conditions. HOW THE RADICALS DO THE JOB. J. Biol. Chem. 2000, 275, 3031 G Henriksson, L Zhang, J. Li, P. Ljungquist, T. Reitberger, G. Pettersson, G. Johansson Is cellobiose dehyrogenase from Phanerochaete chrysporium a lignin degrading enzyme? Biochimica et Biophysica Acta 1480, 83-91 (2000). Karin Jacobson, Bengt Stenberg, Björn Terselius and Torbjörn Reitberger Fracture of some polymers as studied with stress chemiluminescence (SCL) Polymer International 49, 654-658 (2000) Jacobson, K., B. Stenberg, B. Terselius and T. Reitberger Oxidation of Stressed Injection Moulded Polyolefins and Polyamide 6 as Measured by C h e m i l u m i n e s c e n c e Polymer Degradation and Stability 68, 5360(2000) Gábor Merényi, Johan Lind, Gidon Czapski and Sara Goldstein. The decomposition of peroxynitrite does not yield nitroxyl anion and singlet oxygen PNAS, July 18, vol. 97, no. 15, pp8216-8218 Rong Zhao, Johan Lind, Gábor Merényi, Mats Jonsson and Trygve E. Eriksen Reduction Potentials and Kinetics of b-Fragmentation Reactions of 4-Substituted Benzoylthiyl Radicals. J. Phys. Chem. A, Vol. 104, No. 37, 2000, 8524-8526 Daqing Cui, Trygve Eriksen and Ulla-Britt Eklund On metal aggregates in spent fuel, synthesis and leaching of Mo-Ru-Pd-Rh alloy Material Research Society Symposium, Sydney, August 2000, in press. O. Karnland, T. Sandén, L-E Johannesson, T.E. Eriksen, M. Jansson, S. Wold, K. Pedersen, M. Motamedi, B. Rosberg Final Report of the Pilot Part of the Long Term Test of Buffer Material Äspö Hard Rock Laboratory Report 2000. S. Wold, Trygve Eriksen Diffusion of organic colloids in compacted bentonite. The influence of ionic strength on molecular size and transport capacity of the colloids SKB Technical Report TR-00-19, Sep. 2000.

M. Doverskog, U. Jacobsson, B.E. Chapman, P.W. Kuchel and L. Häggström, Determination of NADH-dependent glutamate synthase (GOGAT) in Spodoptera frugiperda (Sf9) insect cells by a selective 1H/15N NMR in vitro assay. J. Biotechnol. 2000, 79, 87-97. D. Rotticci, T. Norin, K. Hult and M. Martinelle, An active-site titration method for lipases. Biochim. Biophys. Acta 2000, 1483, 132-140. F. Lake, L. Hagberg, M. Svensson and C. Moberg, C3-symmetric azaphosphatranes. Collect. Czech. Chem. Commun. 2000, 65, 570-576. K.A.N. Premaratne Bandara, V. Kumar, U. Jacobsson and L-P. Molleyres, Insecticidal piperidine alkaloid from Microcos paniculata stem bark. Phytochemistry 2000, 54, 29-32. T. Røstelien, A-K. Borg-Karlson, J. Fäldt, U. Jacobsson and H. Mustaparta, The plant sesquiterpene germacrene D specifically activates a major type of antennal receptor neuron of the tobacco budworm moth Heliothis virescens. Chem. Senses 2000, 25, 141-148. U. Bremberg, S. Lutsenko, N-F. Kaiser, M. Larhed, A. Hallberg and C. Moberg, Rapid stereoselective C-C, C-O, C-N and C-S couplings via microwave accelerated palladiumcatalyzed allylic substitutions. Synthesis 2000, 1004-1008. F. Rahm, R. Stranne, U. Bremberg, K. Nordström, M. Cernerud, E. Macedo and C. Moberg, Preparation of chiral enantiopure 2(hydroxyalkyl)pyridine derivatives. Use of the chiral pool. J. Chem. Soc., Perkin Trans. 1 2000, 1983-1990. J. Andersson, A-K. Borg-Karlson and C. Wiklund, Sexual cooperation and conflict in butterflies: a male-transferred anti-aphrodisiac reduces harassment of recently mated females. Proc. R. Soc. Lond. B2000, 267, 1271-1275. A-C. Bäckman, P. Anderson, M. Bengtsson, J. Löfqvist, C. R. Unelius and P. Witzgall, Antennal response of codling moth males, Cydia pomonella L. (Lepidoptera; Tortricidae), to the geometric isomers of codlemone and codlemone acetate. J. Comp. Physiol. A 2000, 186, 513-519. N-F. K. Kaiser, U. Bremberg, M. Larhed, C. Moberg and A. Hallberg, Microwave mediated palladium-catalyzed asymmetric allylic alkylation; an example of highly selective fast chemistry. J. Organomet. Chem. 2000, 603, 2-5. L. Vares and T. Rein, A versatile stereocontrolled approach to chiral tetrahydrofuran and tetrahydropyran derivatives via sequential asymmetric Horner-Wadsworth-Emmons and palladium-catalyzed ring closure reactions. Org. Lett. 2000, 2, 2611-2614. K. Sjödin, M. Persson, J. Fäldt, I. Ekberg and A-K. Borg-Karlson, Occurrence and correlations of monoterpene hydrocarbon enantiomers in Pinus sylvestris and Picea abies. J. Chem. Ecol. 2000, 26, 1701-1720. J. Fäldt, M. Eriksson, I. Valterová and A-K. Borg-Karlson, Comparison of headspace techniques for sampling volatile natural products in a dynamic system. Z. Naturforsch. 2000, 55c, 180-188.

N-F. K. Kaiser, U. Bremberg, M. Larhed, C. Moberg and A. Hallberg, Fast, convenient and efficient molybdenum-catalyzed asymmetric allylic alkylation under noninert conditions: An example of microwave-promoted fast chemistry. Angew. Chem., Int. Ed. Engl. 2000, 39, 3596-3598. E. Janin, H. von Schenk, M. Göthelid, U. O. Karlsson and M. Svensson, Bridge-bonded atomic oxygen on Pt(110). Phys. Rev. B 2000, 61, 13144-13149. O. Belda, N-F. Kaiser, U. Bremberg, M. Larhed, A. Hallberg and C. Moberg, Highly stereo- and regioselective allylations catalyzed by Mo-pyridylamide complexes: Electronic and steric effects of the ligand. J. Org. Chem. 2000, 65, 5868-5870. B. Olofsson, U. Khamrai and P. Somfai, A regio- and stereodivergent synthesis of vicamino alcohols. Org. Lett. 2000, 2, 40874089. A. El-Sayed, I. Liblikas and R. Unelius, Flight molecular modeling study on the response of codling moth, Cydia pomonella (Lepidoptera: Tortricidae) to (E,E)-8,10-dodecadien-1-ol and its geometrical isomers. Z. Naturforsch. 2000, 55c, 1011-1017. J. Zhu, R. C. Unelius, K-C. Park, S. A. Ochieng, J. J. Obrycki and T. C. Baker. Identification of (Z)-4-tridecene from defensive secretion of green lacewing, Chrysoperla carnea. J. Chem Ecol. 2000, 26, 2421-2434.

Physical Chemistry Publications N Hedin, I Furó, Accurate Intensities of Broad NMR Lines from Composite Pulse Experiments. J. Magn. Resonance 142 (2000) 32. S Dvinskikh, R Sitnikov, I Furó. 13C PGSE NMR Experiment with Heteronuclear Dipolar Decoupling To Measure Diffusion in Liquid Crystals and Solids. J. Magn. Resonance 142 (2000) 102. I Furó, I Iliopoulos, P Stilbs. Structure and Dynamics of Associative Water-Soluble Polymer Aggregate as seen by 19F NMR Spectroscopy. J. Phys. Chem. B 104 (2000) 485. R Sitnikov, I Furó, U Henriksson. Nuclear Magnetic Resonance Spectrometer with a Frequency Range Extended Below the Megahertz Region. Rev. Scientific Instruments 71 (2000) 450. M Törnblom, R Sitnikov, U Henriksson. A H NMR Study of Order and Dynamics in the Cubic I 1 Phase of the Dodecyltrimethylammonium Chloride/Water System. Luquid Crystals 27 (2000) 943. 2

M Törnblom, R Sitnikov, U Henriksson. Field-Dependent NMR Relaxation Study of Aggregation and Dynamics in Dilute to Concentrated Micellar Decylammonium Chloride Solutions. J. Phys. Chem. 104 (2000) 1529. S Dvinskikh, I Furó. Order Parameter Profile of Perfluorinated Chains in a Lamellar Phase. Langmuir 16 (2000) 2962. S Dvinskikh, I Furó. Combining PGSE NMR with Homonuclear Dipolar Decoupling. J. Magn. Resonance 144 (2000) 142. N Hedin, T Y Yu, I Furó. Growth of C12E8 Micelles with Increasing Temperature. A Convection-Compensated PGSE NMR Study. Langmuir 16 (2000) 7548. S Dvinskikh, I Furó. Cross-Relaxation Effects in Stimulated-Echo-Type PGSE NMR Experiments by Bipolar and Monopolar Gradient Pulses. J. Magn. Resonance 146 (2000) 283. N Hedin, I Furó, P O Eriksson. Fast Diffusion of the Cl- Ion in the Headgroup Region of an Oppositely Charged Micelle. A 35Cl NMR Spin Relaxation Study. J. Phys. Chem. 104 (2000) 8544. W S Price. NMR Gradient Methods in the Study of Proteins. In: Ann. Rep. Prog. Chem, Sect. C 96 (2000) 3. Y Aihara, K Sugimoto, W S Price, K Hayamizu. Ionic Conduction and Self-Diffusion Near Infinitesimal Concentration in Lithium Salt-Organic Solvent electrolytes. J. Chem. Physics 113 (2000) 1981. W S Price, H Ide, Y Arata. Translational and Rotational Motion of Isolated Water Molecules in Nitromethane Studied Using 17O NMR. J. Chem. Physics 113 (2000) 3686. K Hayamizu, Y Aihara, W S Price. Correlation the NMR Self-Diffusion and Relaxation Measurements with Ionic Conductivity in Polymer Electrolytes Composed of CrossLinked Poly(Ethylene Oxide-Propylene Oxide) Doped with LiN(SO2CF3)2 . J. Chem. Phys. 113 (2000) 4785. W S Price, H Ide, Y Arata, O Söderman. Temperature Dependence of the Self-Diffusion of Supercooled Heavy Water to 244 K. J. Phys. Chem. 104 (2000) 5874.

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Publications M Bittererova, T Brinck, H Östmark. Theoretical Study of the Triplet N4 Energy Surface. J. Phys. Chem. A 104 (2000) 11999. T Brinck, A G Larsen, K M Madsen. Solvation of Carbanions in Organic Solvents: A Test of the Polarizable Continuum Model. J. Phys. Chem. B 104 (2000) 9887. P Polizer, J S Murray, E Frice, T Brinck. Two Potential Compounds: Ammonium Superoxide and Ammonium Ozonide. J. Energetic Materials 18 (2000) 89.

Surface Chemistry Publications Ederth, T., and Claesson, P.M. “Forces between Carboxylic Acid Surfaces in Divalent Electrolyte Solutions” J. Colloid Interface Sci. 229, 123-128 (2000) Österberg, M., and Claesson, P.M. “Interactions between Cellulose Surfaces: Effect of Solution pH” J. Adh. Sci. Techn.,14, 603-618 (2000) Claesson, P.M., Blomberg, E., Poptoshev, E. “Surface Forces and Emulsion Stability” in “Encylopedic Handbook of Emulsion Technology”, Ed. J. Sjöblom, Marcel Dekker Inc., (2000) Dedinaite, A., and Claesson, P.M. “Interfacial Properties of Aggregates Formed by Cationic Polyelectrolyte and Anionic Surfactant” Langmuir, 16, 1951-1959 (2000) Poptoshev, E., Rutland, M.W., and Claesson, P.M. “Surface Forces in Aqueous Polyvinylamine Solutions. 2. Interactions between Glass and Cellulose” Langmuir, 16, 1987-1992 (2000) Claesson, P.M., Dedinaite, A., and Poptoshev, E “Polyelectrolyte-Surfactant Interactions at Solid-Liquid Interfaces Studied with Surface Force Techniques” in “Physical Chemistry of Polyelectrolytes”, Ed. Ts. Radeva, Surfactant Science Series Vol., Marcel Dekker, New York, 2000 Dedinaite, A., Claesson, P.M., and Bergström, M. “Polyelectrolyte-Surfactant Layers: Adsorption of Preformed Aggregates versus Adsorption of Surfactant to Preadsorbed Polyelectrolyte” Langmuir, 16, 5257-5266 (2000) Rundlöf, M., Karlsson, M., Wågberg, L., Poptoshev, E., Rutland, M. and Claesson, P. “Application of the JKR Method to the Measurement of Adhesion to Langmuir-Blodgett Cellulose Surfaces” J. Colloid Interface Sci., 230, 441-447 (2000) Claesson, P.M., Bergström, M., Dedinaite, A., Kjellin, M., Legrand, J.-F., and Grillo, I. “Mixtures of Cationic Polyelectrolyte and Anionic Surfactant Studied with Small-Angle Neutron Scattering” J. Phys. Chem. B, 104, 11689-11694 (2000) Rojas, O.J., Ernstsson, M., Neuman, R.D., and Claesson, P.M. “X-ray Photoelectron Spectroscopy in the Study of Polyelectrolyte Adsorption on Mica and Cellulose” J. Phys. Chem B, 104 10032-10042 (2000) Bergström M and Pedersen JS “A small-angle neutron scattering study of surfactant aggregates formed in aqueous mixtures of sodium dodecyl sulphate and didodecyldimethylammonium bromide” J. Phys. Chem. B 104, 4155-4163 (2000) Bergström M and Eriksson JC “A theoretical analysis of synergistic effects in mixed surfactant systems” Langmuir 16, 7173-7181 (2000) Bergström M “Thermodynamics of anisotropic surfactant micelles I. The influence of the curvature free energy on the micellar size and shape” J. Chem. Phys. 113, 5559-5568 (2000) Bergström M “Thermodynamics of anisotropic surfactant micelles II. A molecular interpretation of the micellar curvature free energy” J. Chem. Phys. 113, 5569-5579 (2000)

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Imae T, Kato M and Rutland MW “Forces between two glass surfaces with adsorbed hexadecyltrimethylammonium salicylate” Langmuir 16, 1937 -1942 (2000) Ederth, T. and Liedberg, B. Influence of wetting properties of the longrange “hydrophobic” interaction between selfassembled alkylthiolate monolayers Langmuir 16, 2177-2184 (2000) Grant LM, Ederth T and Tiberg F Influence of surface hydrophobicity on the layer properties of adsorbed nonionic surfactants Langmuir 16, 2285-2291 (2000) Bergström L and Blomberg E Probing polymeric stabilization in nonaqueous media by direct measurements J Am Ceram Soc 83, 217-219 (2000) Dedinaite A and Campbell B Interactions between mica surfaces across triglyceride solution containing phospholipid and polyglycerol polyricinoleate Langmuir 16, 2248-2253 (2000) Österbeg, M The effect of cationic polyelectrolyte on the forces between two cellulose surfaces and between one cellulose surface and a mineral surface J. Colloid Interface Sci., 229, 620-627 (2000) Boschkova, K., Kronberg, B., Rutland, M. and Imae, T. Visco-elastic properties of thin surfactant films studied with the tribological surface force apparatus. 9th Nordic Symposium on Tribology NORDTRIB 2000 (VTT Symp. 2000, 202, 658-665) Boschkova, K., Elvesjö, J., and Kronberg, B. Frictional properties of lyotropic liquid crystalline mesophases at surfaces Colloids Surf. A 166 67-77 (2000) Poptoshev, E., Carambassis, A., Österberg, Claesson, P.M., and Rutland, M.W. Comparison of model surfaces for cellulose interactions: elevated pH Progr Colloid Polym Sci 116: 79-83, 2000 Dedinaite, A., Claesson, P.M., Nygren, J., and Iliopoulos, I. Interactions between Surfaces Coated with Cationic Hydrophobically Modified Polyelectrolyte in Presence and Absence of Oppositely Charged Surfactant Prog. Colloid Polymer Sci., 116 84-94, (2000) Bogdanovic, G., Meurk, A., and Rutland, M.W. Tip friction - artefact and torsional spring constant determination Colloids Surf. B 19, 397-405 (2000)

Theoretical Chemistry Ab initio g-tensor calculations of the thioether substituted tyrosyl radical in galactose oxidase M. Engström, F. Himo, and H. Ågren, Chem. Phys. Lett. 319, 191 (2000). Ab initio study of the PtC molecule. A new assignment of the red bands. B. Minaev, Phys. Chem. Chem. Phys., 2, 2851 (2000) Bond-distance-dependent decay probability of the N 1s-p* core-excited state in N2. M. N. Piancastelli, R. F. Fink, R. Feifel, M. Bässler, S. L. Sorensen, C. Miron, H. Wang, I. Hjelte, O. Björneholm, A. Ausmees, S. Svensson, P. Salek, F. Kh. Gel’mukhanov, and H. Ågren, J. Phys. B, 33, 1819-1826 (2000). Calculations of valence electron binding energies using Kohn-Sham theory and transition potentials. O. Plashkevych, H. Ågren, L. Karlsson, and L.G.M. Pettersson. J. Electron Spectrosc., 106 (2000) 51-63 Continuum modelling of multi-mode vibronic structure in NEXAFS T. Privalov, O. Plashkevych, F. Gel’mukhanov, and H. Ågren, J.Chem. Phys., 113, 3734 (2000). Density Functional Calculations of Electronic g-Tensors Using Spin-Orbit Pseudopotentials and Mean-Field All-Electron Spin-Orbit Operators O. L. Malkina, J. Vaara, B. Schimmelpfennig, M. Munzarova, V.G. Malkin and M. Kaupp, J.Am.Soc. 2000, 122, 9206-9218 (2000) Direct experimental measurement of donation / backdonation in unsaturated hydrocarbon bonding to metals. L. Triguero, A. Föhlisch, P. Väterlein, J. Hasselström, M. Weinelt, L.G.M. Pettersson, Y. Luo, H. Ågren, A. Nilsson, J. Am. Chem. Soc, 122. 12310 (2000) Doppler effect for bound nuclear motion and its manifestation in resonant photoemission of oriented systems P. Salek, F. Gel’mukhanov, T. Privalov and H. Ågren, Chem. Phys. Lett., 328, 425 (2000). Doppler splitting at in-flight Auger decay of dissociating oxygen molecules: The localization of delocalized core holes O. Björneholm, M. Bässler, A. Ausmees, I. Hjelte, R. Feifel, H. Wang, C. Miron, M.N. Piancastelli, S. Svensson,S.L. Sorensen, F. Gel’mukhanov and H. Ågren, Phys. Rev. Letters, 84, 2826 (2000) Electronic and vibronic contributions to twophoton absorption of molecules with multibranched structures P.Macak, Y. Luo, P.Norman and H. Ågren, J.Chem. Phys. 113, No 17, 7062-7071 (2000) Ground and excited states of PtCH2+: assessment of the no-pair Douglas-Kroll ab initio model potential method Rakowitz F, Marian CM, Schimmelpfennig B, Phys.Chem.Chem.Phys. 2000,2,2481 (2000) High-Resolution Spectroscopy of the A-X Band System of MoN N. Andersson, B. Minaev, Physica Scripta., 62, 417-424, 2000 (2000) Hydrogen bonding to the tyrosyl radical analyzed by ab initio g-tensor calculations M Engström, F Himo, A Gröslund, O Vahtras, B. Minaev and H Ågren, J. Phys. Chem. A 104, 5149 (2000) Kramers-Heisenberg and Weisskopf-Wigner descriptions of resonant x-ray Raman scattering H. Ågren and F.Gel’mukhanov, J.Electr.Spectr.Rel.Phen. 110, 153 (2000) MCSCF and DFT calculations of EPR parameters of sulfur centered radicals M Engström, O. Vahtras and H Ågren, Chem. Phys. Letters 328, 483 (2000).

Publications - Diploma Work – Dissertations Modelling of dynamic molecular solvent properties using local and cavity field approaches P.Macak, P.Norman, Y.Luo and H. Ågren, J.Chem.Phys. 112, No 4, 1868-1875 (2000) Nonlinear optical susceptibilities of fullerenes in the condensed phase Y. Luo, P. Norman, P. Macak and H. Ågren, Phys. Rev. B 61, 3060 (2000) Observation of a continuum-continuum interference in ultrafast dissociating core-excited molecules R. Feifel, F. Burmeister, P. Salek, M. N. Piancastelli, M. Bässler, S. L. Sorensen, C. Miron, H. Wang, I. Hjelte, O. Björneholm, A. Naves de Brito, F. Kh. Gel’mukhanov, H. Ågren and S. Svensson, Phys. Rev. Letters, 85, 3133 (2000). On the validity of the equivalent cores approximation for computing X-ray photoemission and photoabsorption spectral bands O. Plashkevych, T. Privalov, H. Ågren, V. Carravetta, K. Ruud, Chem. Phys., 260, 11 (2000) Oxygen Absorption Below and Near the Herzberg I Continuum. Ab initio Calculation of the Transitions Probability from Metastable States. B. Minaev, Phys. Chem., 252, 25 (2000). Resonant X-ray Raman Scattering in a Laser Field F. Gel’mukhanov, P. Cronstrand, and H. Ågren, Phys.Rev. A 61, No 2, 2503 (2000) Resonant X-ray Raman scattering involving avoided crossings in the final state potential energy curves. P. Salek, R.F. Fink, F. Gel’mukhanov, M.N. Piancastelli, R. Feifel, M. Bässler, S. L. Sorensen, C. Miron, H. Wang, I. Hjelte, O. Björneholm, A. Ausmees, S. Svensson, and H. Ågren, Phys. Rev. A, 62, 062506 (2000)

Diploma Work Analytical Chemistry Biomarker Studies on Wound Repair Fluids by Capillary Electrophoresis Theres Redeby ( Janunary 2000) Evaluation of In-Line Near Infrared Spectroscopy Applied to Fermentations using Escherichia Coli, Peter Aizawa ( January 2000)

Inorganic Chemistry Farideh Jahlilevand: PhD thesis “Structure of Hydrated Ions and Cyano Complexes by XRay Absorption Spectroscopy’’ (May 2000)

Kristina Neimert-Andersson, Synthesis of some novel heterocycles using a solid phase approach. Thomas Lenz, Manganese complexes designed for artificial photosynthesis. Synthesis and use as epoxidation catalysts. Christina Borg, Solid phase synthesis of quinolines using a novel traceless linker.

Physical Chemistry R Eklund: “A Quantum Chemical Study of the Baeyer-Villiger Reaction in Modofied Enzymes and in Solution”.

Patric Lindqvist-Reis: PhD thesis “Strucuture of Solvated Metal Ions’’ (June 2000)

M Åberg: “An Image-Processing Approach to Quantitative Structure-Retention Relationships Using Pulse-Coupled Neural Networks”.

Peter Nagy: PhD thesis ‘‘Studies of Formation Kinetics of Platinum-Thallium MetalMetal Bond’’

N Fevrier: “Foam Drainage Studied by Nuclear Magnetic Resonance”.

Nuclear Chemistry

E Winterfors: “Optimisation of Single Transition Cross Polarisation”.

Magnus Carlsson The Effect of Antioxidants on Amino Acid and ProteinOxidation

Surface Chemistry

Paula Andersson Lithium Sorption on Bentonite Clay Ann- Charlotte Nordlund Sorption av technetium på titanoxid ur autentisk upparbetningslösning. Margaretha Carlsson Fysikalkemisk undersökning av ytkontamination på kärnbränslebehållare

Magnus Johnson “Surface Analysis of Liquid Water Microjets by FTIR- and Raman Spectroscopy”.

Dissertations Analytical Chemistry The following disputation for the PhD degree have taken place during 1998:

Response Theory Calculations of Two-photon Absorption Cross Sections. Y. Luo, P. Norman, and H. Ågren, Nonlinear Optics, 26, 153 (2000).

Diploma work (incl. Eramus students)

New Optical Detection Methods for Capillary Electrophoresis, Liquid ChromatoGraphy and Biosensors, Anders Hanning, April 2000

Emil Görnerup, Indium mediated allylation reactions in steroid side-chain synthesis.

Sample Handling in Nanoscale Chemistry, Erik Litborn May 2000

Simulations of vibronic profiles in two-photon absorption P. Macak, Y. Luo, and H. Ågren, Chem. Phys. Lett., 330, 447-456 (2000)

Nils Rackelman, Enantioselective allylic substitutions catalyzed by [(hydroxylalkyl)(pyrrolidinyl)methyl)pyridine]- and [alkoxyalkyl)((pyrrolidinyl)methyl)pyridine]-palladium complexes.

The following disputation for the Licentiate degree have taken place during 1998:

Solvent induced two-photon absorption of pushpull molecules Y. Luo, P. Norman, P. Macak and H. Ågren, J. Phys. Chem. A, 104, 4718 (2000) Spin Uncoupling in Methane Activation B. F. Minaev, Bulletin of the Polish Academy of Science. Chemistry, Vol. 48, p.131-142, 2000 (2000) Spin-orbit coupling constants from coupledcluster response theory Christiansen O, Gauss J, Schimmelpfennig B, Phys. Chem. Chem. Phys. 2, 965-971(2000) Temperature dependence and Debye-Waller factors for resonant x-ray Raman scattering in solids F. Gel’mukhanov, T. Privalov, and H. Ågren, Phys. Rev. B 62, 13996 (2000). Theoretical calculations for excited state absorption P. Cronstrand, O. Christiansen, P. Norman and H. Ågren, Phys. Chem. Chem. Phys. 2000, 2, 5357 (2000) Vibronic structure fingerprints in NEXAFS: a theoretical study of 2-mercaptobenzoxazole. O. Plashkevych, H. Ågren, V. Carravetta, G. Contini, G. Polzonetti, Chem. Phys. Letters, 327, 7 (2000) X-ray Raman scattering under pulsed excitation F. Gel’mukhanov, P. Salek, A. Shalagin, and H. Ågren, J. Chem. Phys. 112, No 13, 5593-5603 (2000) Ab initio calculations of molecular resonant photoemission spectra V. Carravetta, H. Ågren, O. Vahtras, and H.J.Aa. Jensen, J. Chem. Phys. 113, 7790 (2000).

Organic Cemistry

Josefin Utas, Nya ligander för osmiumkatalyserad dihydroxylering av alkener. Mark Sundberg (SU), Attemps to synthesize a chiral bis(oxazoline) for catalysis of a DielsAlder reaction through activation and positional control of both substrates. Fredrik von Kieseritzky, Synthesis of d,lBiTOT – A novel building block for electroactive oligomers and polymers. Ann-Charlotte Almqvist (KTH College of Engineering), Host selection of Tomicus piniperda L. Monoterpene composition related to attack frequence in the shoot feeding phase. Tobias Ginman, Thiophene based ligands for potential acetylcholinesterase inhibitors. Jan Blid, New fused heterocyclic and aromatic systems; 1,2-dichloroethane-1,2-bis(sulphenyl chloride) as a building block. Johann Grognux, Enantioselective allylic substitutions catalyzed by [(hydroxyalkyl)((pyrrolidinyl)methyl)pyridine]- and [(tertbutyldimethylsilyloxyalkyl)((pyrrolidinyl)methyl)pyridine]palladium complexes. Olivier Schicke, Catalytic oxidation of light alkenes by activated metalloporphyrins. Nicolas Pradeille, Synthesis and intramolecular radical cylization of trans-N-butyl-Nchloro-(2-tert-butyl-hex-4-enyl)amine.

Spectrometriy in Process Analytical Chemistry. Application to Kraft Cooking Liquors. Yang Xiaotion, May 2000 On-Line Measurements in the Production of Alkyl Ketene Dimer (AKD) Fredrik Aldaeus (March 2000) Capillary Electrophoresis of Hydrophobic Proteins and Peptides Gustav Sundqvist (march 2000) Trypsin-Coated Reactor for Myoglobin Digestion Delphine Marel ( June 2000)

Nuclear Chemistry Martin Ragnar (Ph D thesis) On the Importance of Radical Formation in Ozone Bleaching Erik Johansson (Licentiate thesis) Free Radical Mediated Cellulose Degradation During High-Cosistency Ozone Bleaching Conditions.

Didier Rotticci, Understanding and engineering the enantioselectivity of Candida antarctica lipase B towards sec-alcohols. Diss. (2000). Jenny Fäldt, Volatile constituents in conifers and conifer-related wood-decaying fungi. Biotic influences on the monoterpene compositions in pines. Diss. (2000). Berit Olofsson, A regio- and stereodivergent synthesis of vic-amino alcohols. Licentiate thesis (2000). Ba-Vu Nguyen, Chiral building blocks for synthesis of pine sawfly sex pheromones. Diss. (2000). Björn Hedman, Tall oil products as raw material for surfactant synthesis. Licentiate thesis (2000).

Physical Chemistry M Törnblom: “Field Dependent Nuclear Magnetic Relaxation in Surfactant Solutions and Cubid Phases”. M Österberg: “On the Interactions in Cellulose Systems: Surface Forces and Adsorption”. R Sitnikov: “Nuclear Magnetic Relaxation in Micellar Solution and Lyotropic Liquid Crystals. Tools and Applications”. N Hedin: “NMR Studies of Complex Fluids and Solids Formed by Surfactants”. B Folmer: “Physico-Chemical Characterisation of Novel Surfactants”.

Surface Chemistry Monika Österberg “On the Interactions in Cellulose Systems: Surface Forces and Adsorption”, PhD-thesis Peter Hansen “Colloidal Aggregation and Film Formation in Two Dimensions”, PhD-thesis Britta Folmer, “Physic-Chemical Characterisation of Novel Surfactants”, PhD-thesis Pernilla Liljekvist, “Surface Tension Studies of Mixed Nonionic-Anionic Surfactant Systems”, Lic-thesis Mark Plunkett, “Dynamic Surface Force Measurements between Polymer Coated Surfaces”, Lic-thesis Evgeni Poptoshev “Surface Interactions Related to Papermaking Systems”, Lic-thesis

Theoretical Chemistry Doctoral Thesis: Olexandre Plachkeytch: “X-ray absorption near the edge”, 13/5 2000. Licentiat Thesis: Timofei Privalov: “X-ray scattering by molecules, surface-adsorbates and solids with a coupling to the nuclear motion”, 12/ 5 2000. Licentiat Thesis: Peter Macak: Modelling of Solvent Effects on Non-linear Optical properties”, 12/5 2000.

Organic Chemistry Raimondas Mozuraitis, Chemical communication in leaf mining moths of the genus Phyllonorycter. Diss. (2000). Jan Holmbäck, Magnetic moments - NMR spectroscopy in lipid science. Diss (2000). Ulf Bremberg, Asymmetric catalysis: Ligand design and microwave acceleration. Diss. (2000).

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