A time-dependent wave packet approach to atom–diatom reactive collision probabilities: Theory and application to the H+H2 (J=0) system

Abstract

This paper describes a new approach to the study of atom–diatom reactive collisions in three dimensions employing wave packets and the time-dependent Schrödinger equation. The method uses a projection operator approach to couple the inelastic and reactive portions of the total wave function and optical potentials to circumvent the necessity of using product arrangement coordinates. Reactive transition probabilities are calculated from the state resolved flux of the wave packet as it leaves the interaction region in the direction of the reactive arrangement channel. The wave packet does not need to be propagated into the asymptotic reactive region in order to determine accurate vibrationally resolved, but rotationally summed reaction probabilities. The present approach is used to obtain such vibrationally resolved reaction probabilities for the three-dimensional H+H2 (J=0) hydrogen exchange reaction, using a body-fixed system of coordinates.