Rotationally inelastic transitions between the fine-structure levels of the 3Σ−g electronic ground state of O2

Abstract

Infinite-order sudden calculations, including the effects due to the coupling of the rotational and the electronic spin angular momenta, are reported for the inelastic differential and integral cross sections of O2 in its 3Σ−g electronic ground state, scattering against He and Ar. These calculations demonstrate that measurements of differential cross sections that fully resolve the dependence on the O2 fine-structure levels can in fact provide detailed information about the anisotropy of the van der Waals interaction potential much more readily than measurements of the total or unresolved j state inelastic differential cross sections. Several propensity rules for transfer of rotational energy in 3Σ electronic states, which were derived recently by Alexander and Dagdigian [J. Chem. Phys. 79, 302 (1983)] in the large-j limit, are found to be valid for O2 for all values of j.