Effect of rovibrational coupling on the dynamics of ionic systems: the Kr-O2+case

Abstract
Various quantum decoupling and semiclassical methods are used to calculate cross sections for rotational and rovibrational transitions in O2+ colliding with Kr. A general analysis of time scales for rotational and vibrational excitations and of coupling strengths for the corresponding potentials is used to review the standard decoupling methods that treat separately vibrations and rotations in atom-molecule collisions. When such decoupling is applied to strongly interacting ionic systems and to heavy particles, it is found to fail rather dramatically and to be brought back to reliable values only when fully coupled rovibrational equations are used to treat the dynamics.