Theoretical study of the anion of lithium hydride

Abstract

The potential energy curves of the ground state of LiH and LiH- have been obtained by accurate ab initio configuration interaction calculations. The bond length, dissociation energy, and spectroscopic constants obtained from the potential curve of LiH are within 1% of corresponding experimental values. The results for LiH- are Re = 3.15±0. 03α0, De = 2.10±0.02 eV, D0 = 2.03±0.02 eV, and ωe = 1179±11 cm-1. The calculated adiabatic electron affinity of LiH is 0.32 eV with an estimated error limit of ±0.02 eV. A semiempirical method for calculating diatomic molecular electron affinities is proposed. A detailed comparison of the current CI calculation with a previous equations-of-motion calculation is presented. Copyright © 1977 American Institute of Physics.