Theoretical calculations of a new potential energy surface for the H + Li 2 reaction

Abstract

We present a new accurate potential energy surface (PES) for the ground state H + Li 2 reaction from full configuration interaction and pseudo-potential calculations. The electronic energies were computed using an atomic orbital basis of 6-311G (2df, 2pd) quality. The results were fitted using a Bond Order polynomial expansion of eighth order. A topological study verified that the geometric configurations, energies, vibrational spectroscopic constants for the complex (HLi 2), reactant (Li 2), and the product (LiH) of the exothermic (about 34 kcal/mol) H + Li 2 fitted PES are in excellent agreement with the experimental data available in the literature. Furthermore, as a preliminary test, quasiclassical trajectories are integrated on the fitted surface to determine the reactive cross-section of the new PES.