A GLOBAL POTENTIAL-ENERGY SURFACE FOR ARH2

We describe an analytic representation of the ArH2 potential energy surface which well reproduces the results of extensive ab initio electronic structure calculations. We also give an empirical modification of the function designed to improve agreement with experimental estimates of the van der Waals minimum. The analytic representation smoothly interpolates between the H + H and strong bonding H-2 limits. In the fitting process, an accurate reproduction of regions of the potential expected to be important for high temperature (approximately 3000 K) collision processes is emphasized. Overall, the analytic representation well reproduces the anisotropy and H-2 bond length dependence of the input data.