Rates for dissociative recombination of LiH+ ions

Abstract

We review recent progress in developing a theoretical treatment of the dissociative recombination (DR) process for the LiH+ molecule, in which a low energy electron is captured and causes the molecule to dissociate into neutral fragments. This e+LiH+ system is prototypical of the indirect class of DR processes, in which the incident electron destroys the molecule through Rydberg capture pathways. The conventional mechanism characteristic of most species with a high DR rate, which normally involves direct capture into a dissociative resonance potential curve, is entirely absent here. We have adopted ab initio multichannel quantum defect theory (MQDT) and a rovibrational frame transformation based on Siegert pseudostates to calculate indirect dissociative recombination for this simple diatomic ion. It is based on a set of ab-initio quantum defects as functions of the internuclear distance, which have been calculated using the R-matrix approach. The calculated DR rate coefficient is found to agree with recent experimental data [1].