Resonant and inelastic transitions in collision between HCl molecules

Abstract

Transition probabilities and cross sections for rotational transitions from the initial state j01=0, j02=1 have been calculated for an initial relative kinetic energy E0=0.025 eV. The semiclassical exponential approximation has been used. All possible single-molecule and simultaneous transitions as well as intermultiplet transitions have been included with all energetically accessible states. These transitions are caused by the anisotropic short-range, dispersive, inductive, and electrostatic interactions. The influence of pairs of resonating channels on the various inelastic transitions has been discussed. The limitations of the first order perturbation theory calculations are clearly brought out. The importance of various factors determining the relative magnitudes of the cross sections are shown.