A new four-dimensional ab initio potential energy surface and predicted infrared spectra for the Ne–CS2 complex

Abstract

ABSTRACTA new four-dimensional (4D) ab initio potential energy surface (PES) for Ne–CS2 involving the Q1 and Q3 normal modes for the ν1 symmetric stretching vibration and ν3 antisymmetric stretching vibration of CS2 is presented. The PES is constructed at the coupled-cluster singles and doubles with noniterative inclusion of connected triples [CCSD(T)]-F12 level with a large basis set including midpoint bond functions. Two vibrationally averaged potentials with CS2 at the vibrational ground and ν1 + ν3 excited states are generated from the 4D potential. Each potential contains a T-shaped global minimum and two equivalent linear local minima. The rovibrational energy levels and bound states are calculated employing radial discrete variable representation/angular finite basis representation and the Lanczos algorithm. In addition, the predicted band origin shift is 0.2514 cm−1 for Ne–CS2. The spectroscopic parameters are also predicted.