Dynamics of the endothermic reaction He+H+2 →HeH++H on an accurate a b i n i t i o potential-energy surface

We report herein a successful analytic fit of the ab initio potential-energy surface of McLaughlin and Thompson for the ground state HeH+2 system and also the results of a three-dimensional quasiclassical trajectory study of the exchange reaction over a wide range of vibrational states and relative translational energies of the reactants. While there is good agreement between theory and experiment in many respects, there are some quantitative discrepancies remaining with respect to some of the experimental results.