Rovibrational calculations without model Hamiltonians: The infrared and microwave spectra of thiopropynal

Abstract

Rovibrational configuration interaction theory has been used to study the rotational spectrum and low lying rovibrational states of thiopropynal, a molecule, which has recently been detected in an interstellar cloud. Geometrical parameters, fundamental vibrational transitions and spectroscopic constants are also provided. All calculations rely on an $n$-mode representation of the multidimensional potential energy surface, which has been obtained from explicitly correlated coupled-cluster approaches including core correlation effects and an approximate treatment of high-order coupled-cluster terms. Comparison with experimental data is provided for several properties and the agreement was found to be excellent in most cases.