Vibrational and Rotational Excitation in Molecular Collisions

Abstract

Publisher Summary This chapter focuses on the vibrational and rotational excitation in molecular collisions. The dynamics of a molecular collision is governed by the interaction forces between and within the colliding molecules. For given molecular electronic states, these can be summarized in potential energy functions of the respective internuclear distances and, when excluding electronic transitions, only one potential energy surface is relevant for the molecular collision. Differential vibrationally and rotationally inelastic scattering experiments measure the angular dependence of fully resolved state-to-state cross sections or, when internal state resolution cannot be completely achieved, inelastic excitation cross sections for energetically close groups of states. The joint experimental and theoretical studies of microscopic vibration–rotation inelastic cross sections are also well suited for the understanding and quantitative prediction of macroscopic phenomena such as gas-phase transport properties and internal-state relaxation processes of non-spherical molecules onto firmer microscopic grounds.