A new ab initio potential energy surface for the Ne-H2 interaction

A new accurate three-dimensional potential energy surface for the Ne-H-2 system, which explicitly takes into account the r-dependence of the H-2 vibration, was determined from ab initio calculations. It was obtained with the single and double excitation coupled-cluster method with noniterative perturbational treatment of triple excitation [CCSD(T)]. Calculations was been performed using the augmented correlation-consistent polarized quintuple zeta basis set (aug-cc-pV5Z) for the three atoms. We checked the accuracy of the present ab initio calculations. We have determined, using the new Ne-H-2 potential energy surface, differential cross-sections for the rotational excitation of the H-2 and D-2 molecules in collision with Ne and we have compared them with experimental results of Faubel et al. [M. Faubel, F. A. Gianturco, F. Ragnetti, L. Y. Rusin, F. Sondermann, U. Tappe, J. P. Toennies, J. Chem. Phys. 101 (1994) 8800]. The overall agreement confirms that the new potential energy surface can be used for the simulation of molecular collisions and/or molecular spectroscopy of the van der Waals complex Ne-H-2. (C) 2009 Elsevier B.V. All rights reserved.