Ab initio potential energy surface and rovibrational bound states for the Kr–HCCCN complex

The first ab initio potential energy surface for Kr–HCCCN was calculated using the coupled-cluster singles and doubles with noniterative inclusion of connected triples [CCSD(T)] with a large basis set containing bond functions. The potential has a T-shaped global minimum and a local linear minimum with the Kr atom facing the H atom. The radial discrete variables representation (DVR)/angular finite basis representation (FBR) method and the Lanczos algorithm were employed to calculate the rovibrational energy levels for three isotopomers 84Kr–HCCCN, 82Kr–HCCCN, and 86Kr–HCCCN. The spectroscopic constants for the ground and the first excited states of Kr–HCCCN were predicted.