With this grant in the Theoretical and Computational Chemistry Program of the Chemistry Division, Professor Schatz will develop new theoretical and computational methods for describing unimolecular and bimolecular reactions and other collision processes in the gas phase. The research will lead to a deeper understanding of the mechanism and rate of these important chemical reactions. The following areas will be investigated: (1) quantum mechanical methods for describing atom-diatom bimolecular reactions and dissociative photoprocesses, (2) classical and quantum methods for studying collisional relaxation of highly excited molecules by other molecules, and (3) quasiclassical methods for simulating state to state dynamics in chemical reactions involving triatomic and larger molecules.