On the evaluation of the classical phase for reactive molecular collisions in semiclassical collision theory

Abstract

A new formula for the generator of a cartesian to action-angle change of variables for a Morse oscillator is presented. It can be used to calculate the classical phase of semiclassical collision theory for both inelastic and reactive collisions. In the reactive case, the calculation of the phase is equivalent to using action-angle variables for the initial (final) oscillator during the first (second) part of the collision. As an example, application is made to the collinear reactions H + Cl2(n 1→HCl(n 2=2) + Cl and H + F2(n 1=0)→HF(n 2=6) + F for an energy range where there is complete transmission and two contributing real root trajectories.