Professor, Department of Chemistry, Graduate School of Science, Kyoto University, JAPAN

Email: shigeki@kuchem.kyoto-u.ac.jp
WWW: http://kuchem.kyoto-u.ac.jp
/riron/index.html

Japan IBM Science Award (1992)

Author of:

About 120 research papers in theoretical chemistry.

Chemical Dynamics of Molecules in Solution: Developments of realistic potential models for describing chemical reaction dynamics in solution. The charge response kernel (CRK) model is a unique polarizable molecular model derived directly from ab initio electronic structure methods. It has been successfully applied to study many dynamics processes in solution such as the anomalous slow diffusion of radical species in alcohol and fast vibrational relaxation of azide anion in aqueous solution. A new model Hamiltonian to calculate the ground and excited potential energy surfaces of transition metal aqueous solutions has been also developed based on the CRK model.

Electronic structure theories for molecules in solution: The reference interaction site self-consistent field (RISM-SCF) theory is an ab initio electronic structure method combined with the RISM integral equation theory for molecular liquids. It has an advantage that it maintains molecular aspects of solvents. The RISM-SCF theory was further extended to incorporate the solvent thermal configurational and electronic fluctuations and to describe time-dependent processes such as dynamic Stokes shift. A solution reaction path Hamiltonian model for describing dynamics of solution phase reactions was developed within the framework of RISM-SCF theory.

Chemical Reactions in the Gas Phase: Full six-dimensional quantum dynamics calculations on HFCO employing ab initio potential energy surface fully explained the mode specific dissociation rates experimentally observed. The eigenstate resolved rate constants were obtained for the spin-forbidden dissociation reactions to compare with the random matrix based statistical theory of the distribution of state-specific rate constants. Quantum dynamics studies of excited state reactions have been also carried out.