Computational Study of Nonadiabatic Effects in Atom-Molecule Reactive Scattering

摘要

This report describes an eighteen month research program designed to develop theoretical methods for studying nonadiabatic effects in atom-diatomic molecule collisions. A method for computing accurate three-dimensional reactive scattering wavefunctions has been developed. A method for including several electronic states in a molecular scattering calculation has been implemented. An interactive formulation of the exchange kernal approach to reactive scattering has been examined, and is found to have features that warrant its development for problems involving large numbers of coupled equations. A version of the method incorporating finite element techniques has been programmed and preliminary testing has begun on HF-HF self-relaxation. The current code needs refinement and is presently not programmed to allow for reaction. It is anticipated that this approach will allow treatment of several thousand coupled equations on the new generation of supercomputers. Applications of these numerical methods are being made to several molecular systems, including collisions of atomic sodium, oxygen and fluorine with molecular hydrogen.