Determining anisotropic intermolecular potentials for van der Waals molecules

Abstract

The effects of model-dependence and statistical correlation upon the determination of a potential energy surface from the spectroscopic data for isotopic H2–Ar van der Waals complexes, are critically examined. The new potential thus obtained for this system has the correct theoretical long-range behaviour, and yields predicted differential scattering cross-sections and orbiting resonance energies in good accord with experiment. It is also shown that the secular equation method previously applied to H2+ inert gas complexes may also be successfully used to calculate the properties of much more strongly anisotropic species, such as HCl–Ar.