QUANTUM-MECHANICAL CALCULATIONS OF THE COLLINEAR REARRANGEMENT REACTION HE-HEH++H AT ENERGIES UP TO THE DISSOCIATION THRESHOLD(H2+[)

A quantum-mechanical study has been carried out for a collinear rearra ngement reaction He + H-2+ --> HeH+ + H both on a diatomics-in-molecul es semi-empirical surface and on a fitted ab initio surface. The calcu lation for the fitted ab initio surface has been carried out with a fi ne mesh in a broad range of energies up to the dissociation threshold. The reaction probabilities for the H-2+ molecule initially in highly excited vibrational states are also reported.