Dr. Stephen Gray is supported by a grant from The Theoretical and Computational Chemistry Program to perform theoretical studies of the dissociation dynamics of van der Waals clusters. Classical dynamics and time-dependent quantum dynamics will be used to study the bottlenecks to energy flow and chemical reactivity in these systems. Systems which have been chosen for study are ones for which excellent experimental results already exist for comparison with the theoretical calculations. Numerically exact classical and time-dependent quantum dynamics calculations on several experimentally interesting van der Waals systems will be carried out. Nonlinear resonances between vibrational and/or rotational modes, and phase space bottlenecks to energy flow and chemical reactivity will be examined in hopes of explaining the lifetimes and product distributions of these compounds. A variety of nonlinear dynamics ideas and methods including, for example, simple phase space projections, local estimates of frequencies, and exponential separations will be applied to each system of interest. Gray also proposes to develop an alternative to the very successful RRKM theory for estimating van der Waals unimolecular decomposition rates.
