Quasi-classical trajectory study of the adiabatic reactions occurrion the two lowest-lying electronic states of the LiH2+ systemng

Quasi-classical trajectory calculations have been performed on the adiabatically allowed reactions taking place on the two lowest-lying electronic states of the LiH2+ system, using the ab initio potential energy surfaces of Martinazzo et al. (J. Chem. Phys., 2003, 119, 11 241). These reactions comprise: (i) the exoergic H-2 and H-2(+) formation occurring through LiH+ + H and LiH + H+ collisions in the ground and in the first electronically excited state, respectively; (ii) the endoergic ( ground state) LiH+ dissociation induced by collisions with H atoms; and (iii) the endoergic ( excited state) Li + H-2(+) -> LiH + H+ reaction. The topic is of relevance for a better understanding of the lithium chemistry in the early universe. Thermal rate constants for the above reactions have been computed in the temperature range 10-5000 K and found in reasonably good agreement with estimates based on the capture model.