SUDDEN APPROXIMATION FOR COLLISION-INDUCED DISSOCIATION

Collision-induced dissociation (CID) in atom-diatom non-reactive syste ms is studied quantum mechanically by treating the rotational and vibr ational degrees of freedom in a sudden approximation. The collision pr oblem to be solved is reduced to a one-dimensional Schrodinger equatio n with respect to the intermolecular radial distance. Therefore, only the scattering phase shift is an important quantity, and a physical in sight into the collision dynamics can be obtained by observing the dep endence of the scattering phase shift on the molecular orientation and on the internuclear distance of the molecule. The sudden approximatio n is applied to He + H-2 collisions. The present result indicates the applicability of the sudden approximation to CID in general cases of h eavier diatomic or polyatomic molecules.