Accurate ab initio-based DMBE potential energy surface for HLi2(X 2A′) via scaling of the external correlation
College of Physics and Electronics, Shandong Normal
2 Department of Physics, Liaoning University, Shenyang 110036, P.R. China
Received in final form: 22 October 2013
Published online: 22 January 2014
A globally accurate potential energy surface is reported for the electronic ground-state HLi2 by fitting ab initio energies to double many-body expansion formalism. The total 3726 ab initio energies used to map the HLi2 potential energy surface are calculated using the multi-reference configuration interaction method, with their dynamical correlation being semiempirically corrected by the double many-body expansion-scaled external correlation method. The current potential energy surface generates an excellent fit of the ab initio energies, showing a small root-mean squared derivation of 0.636 kcal mol-1. The topographical features of the HLi2 potential energy surface are examined in detail, which concludes that the H + Li2(X 1Σg) → Li + LiH(X 1Σ) reaction is essentially barrierless and the exothermicity is calculated to be 33.668 kcal mol-1, thus corroborates the available experimental and theoretical results.
Key words: Atomic and Molecular Collisions
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag 2014