Research

General area: Exact and natural sciences
Science: Chemistry
Branch: Theoretical chemistry
Approach: Quantum Chemistry

Related Pages at this Site

Present

Since 1998 I work at Tallinn University of Technology (Estonia). In approximate reverse chronological order, I have worked on:

    • Determining the conformation of organic molecules via combined experimental and computational study of proton-proton coupling constants (publication 31).

    • Accurate prediction of tautomeric equilibria in a series of substituted purinamines (publications 29 and 30).

    • Modeling of copper thiolate clusters which are possibly present in copper chaperones - the proteins which transport copper ions in cells, safekeeping the ions which would otherwise poison the organism (publication 27).

    • Conformational study and the interdependence of flexibility and protonation of certain organic bicyclic molecules: bimorpholine and bipiperidine (publications 25, 26, 28).

    • Computational study of the rare oxidation state (II) of silver (publication 24).

    • Modeling of solid-state structures: predicting high-pressure behaviour of sulphur trioxide (publication 20), and studying ion-exchange properties of apatites (publication 23).

    • Modeling of hydrated transition metal complexes, with the goal of predicting aqueous redox potentials of transition metal cations with accuracy comparable to that of available experimental data (publications 19, 21, 22, conference proceedings 1).

Even though the range of problems seems diverse, the common unifying features of all this work are transition metal complexes and flexibility in large organic molecules. Some of the work involves both aspects, and much effort is going into yet-unpublished studies which connect the two areas.

Helsinki: 1996-1998

At University of Helsinki (Finland) I was working on the relativistic effects in quantum chemistry, with the application of ab initio methods and pseudopotentials. At least two longer term goals were set: (1) new species prediction, where we were trying to theoretically map the outlying areas of 'islands of stability' of related chemical compounds, and (2) metallophilic (aurophilic) attraction, the study of the phenomenon of two closed-shell atoms of gold (as well as several other heavy elements) attracting each other in various chemical contexts. This leads to unusually short Au-Au bonds (shorter than in bulk metallic gold) and effects as strange as ions of the same charge attracting each other.

The research on new species has resulted in five papers (numbers 12, 13, 14, 16, 18 in my list of publications). The aurophilic attraction studies yielded two papers (numbers 15 and 17). The latter one also contains some new-species predictions.

University of Florida, 1994-1996

During my two and a half years at University of Florida in Gainesville, I was involved in the development of the Self-Consistent Reaction Field and Polarizable Continuum Models for solvation, including but not limited to the Multi-Cavity variety of the same. I also worked on potential energy surfaces of SN2 reactions. Most of the results have been published; check my publication list for details.

I was also coordinating the technical side of the development of the ZINDO quantum-chemical software package.

University of Tartu, until 1993

During my undergraduate and graduate years in Tartu (Estonia), I worked on various aspects of theoretical chemistry. In particular, I studied polar resonance and its relation to solvent effects and worked on implementing solvation code in quantum-chemical software. For a brief period of time I also worked on quantitative structure-activity relationships, and measured reaction kinetics, but no publications resulted from that.