Possible reaction paths in the LiH2+ chemistry:: a computational analysis of the interaction forces

The present study addresses the problem of establishing from fully ab initio quantum methods some quantitative features of the chemical interactions which play an important role in the ionic lithium chemistry of astrophysical relevance. In particular, the LiH2+ energetics is examined by looking at the various possible chemical channels producing LiH, LiH+, H-2 and H-2(+). An accurate evaluation of the relative energy landscapes as the complex breaks up into its asymptotic partners is presented for the first time. It allows us to clearly select those reactive pathways which can be excluded when setting up a kinetic modeling of the lithium chemistry network in early universe processes. (C) 2001 Elsevier Science B.V. All rights reserved.