Theoretical Spectroscopy and Quantum Dynamics

University Of Chicago, Chicago IL

Investigators

Abstract

John Light of the University of Chicago is supported by the Theoretical and Computational Chemistry Program to develop theoretical methods for the accurate description of quantum dynamics in molecular systems. These new methods will be incorporated into general computer codes to treat classes of larger and "difficult" molecules. The novel quantum methods to be developed are based on two principles: localization (divide and solve-by-parts) and efficient phase space representations. The former permits large problems to be broken into smaller problems; the latter includes two new approaches to highly efficient representations. Applications will be made to clusters such as water trimers, and the quantum dynamics of high-energy, heavy, and/or floppy molecules. Since this research involves the fundamentals of quantum descriptions at the molecular level, the results are expected to be widely useful in reaction dynamics as well as spectroscopy. Theoretical chemistry attempts to understand and predict the behavior of real systems, both microscopic and macroscopic, based on knowledge of the fundamental interactions at the atomic and molecular level. The fundamental processes of interest include reactions in the gas phase, catalytic reactions at surfaces, absorption and emission of radiation, photodissociation, solvation and reactions in condensed phase, electron transfer, and diffusion. Theoretical and algorithmic advances are required in order to assess quantum effects of these larger systems. Quantitative understanding of such processes can lead, for example, to control of combustion processes, synthesis of novel materials, and biological processes.