New bases for the evaluation of interaction energies: An ab initio study of the CO–Ne van der Waals complex intermolecular potential and ro-vibrational spectrum

Abstract

Recently we have derived new efficient basis sets for the evaluation of interaction energies in the X–Y (X, Y = He, Ne, Ar) van der Waals complexes. Here we extend the study to the CO–Ne complex. For this, we start with a systematic basis set study, where the LPol, MLPol and Jensen’s aug-pc-2 basis sets are considered as starting point (for the Ne atom LPol bases are developed). As reference we take interaction energy results obtained with Dunning’s augmented correlation consistent polarized valence basis sets. In all cases we test extensions with different sets of midbond functions. With the selected bases we evaluate CCSD(T) interaction potentials, and to check the potentials further, we obtain the ro-vibrational spectrum of the complex. The results are compared to the available experimental data.