Classical dynamics of vibrational transfer in Li2 A 1Σu+-Ne collisions

Classical trajectory calculations on an ab initio potential surface for the Li2 A1Σu+-Ne system show that vibrationally inelastic collisions at low reagent excitation are dominated by impacts of the atom with the side of the molecule. As molecular excitation increases, impacts nearer the end of the molecule increase in importance. The two classes of collisions are clearly distinguishable in computed velocity-dependent cross sections, and should be observable in some cases as a bimodal angular momentum distribution in velocity-averaged rate constants. We discuss experimental data in light of these observations and suggest measurements that should clearly display evidence of the two mechanisms.