State selected He–HCl collision cross sections

Abstract

Previous calculations of He–HCl collisions at 200 cm⁻¹ are here extended to include some state selected cross sections, namely the integral cross sections for scattering from one jm state to another and some of the corresponding differential scattering cross sections summed over all exit channel magnetic projection quantum numbers, m′. In agreement with the coupled states approximation, the integral cross sections are found to be almost diagonal in m, and the sum of these over the exit channel projection quantum number, m′, to decrease as m increases. The amplitudes of the differential scattering patterns are found to depend on initial m very strongly at large angles, but the positions of the nodes and extrema do not. Although the coupled states approximation predicts all these features qualitatively, it tends to overestimate the size of the effect.