Robert Parsons is supported by the Theoretical and Computational Chemistry Program to theoretically investigate complex dynamics in cluster ions. He uses clusters to discover the microscopic details of solvation, electron transfer, and energy dissipation that distinguish reactions in the condensed phase from their gas-phase analogs. Projects include molecular dynamics simulations of iodine anion photodissociation in carbonyl sulfide clusters, a more rigorous treatment of simulated time-resolved photoelectron spectra, and development of a kinetic theory of vibrational relaxation incorporating solvent evaporation.
Molecular ions in the gas-phase can become solvated by surrounding neutral molecules in much the same way as ions become solvated by water in aqueous solutions. This research establishes connections to condensed phase phenomena by increasing our understanding of cluster dynamics. In particular, the role of strong and long-ranged solute-solvent interactions has not heretofore been investigated in detail. Parson's use of hierarchical models is particularly valuable in delineating the possible limitations of simpler descriptions of these phenomena.
