OH−(X1Σ+) collisions with 4He(1S) at vanishing energies: a quantum analysis of rotational quenching efficiency

Abstract

A newly computed potential energy surface which describes the interaction between the two title partners is employed to evaluate collisional quenching of the rotational levels of the OH−(X1Σ+) anion by 4He atoms at ultralow energies. The calculations are carried out within the exact coupled channel (CC) formalism and both elastic and inelastic quenching cross sections for rotationally ‘hot’ molecules are obtained. The present results indicate the process to be a fairly efficient one and allow us to discuss, in some detail, the qualitative propensity rules on the quenching which can be extracted from calculations at ultralow collision energies.