Polarization and electronic excitation in nonreactive collisions: Basic formulation for quantum calculations of collisions between 2P-state alkali-metal atoms and H2 or D2.

Abstract

The inelastic scattering of two structured systems---for example, an excited atom and a molecule---is considered in the case of nonreactive collisions. Explicit formulas are presented for cross sections corresponding to transitions between arbitrary eigenstates of the two isolated systems. These formulas are then used to derive cross sections for polarization transfer and multipole relaxation in one system when the other system is unpolarized. Both space-fixed and body-fixed formulations are given. Explicit matrix elements are worked out for interactions such as occur between model alkali-metal atoms and rigid-rotor diatomic molecules. An effective interaction method is also discussed and related to an adiabatic-state approach.