Translational cooling versus vibrational quenching in ultracold OH--Rb collisions: A quantum assessment

A new three-dimensional potential energy surface (PES), which describes the interaction between the OH-(X (1)Sigma(+)) anionic molecule and the Rb(S-2) atomic gas has been obtained by using a highly correlated ab initio model of the electronic structure and a large atomic basis set supplemented with a set of midbond Gaussian functions. This accurate PES is being employed to evaluate the OH-(X (1)Sigma(+)) vibrational quenching efficiency induced by collisions with Rb(S-2) at low and ultralow energies. Calculations employ the coupled-channel ansatz to describe the nuclear quantum dynamics and finally show a very marked dependence of the inelastic cross sections and rates, at vanishing collision energies, on the initial vibrational energy content of the partner molecules. The present findings allow us to make specific suggestions on the likely outcomes from energy interplay between the title species within a mixed MOT/Paul Trap environment.