MARVEL analysis of high-resolution spectra of thioformaldehyde (H[formula omitted]CS)

Abstract

We present a comprehensive analysis of the published spectroscopic literature on the main isotopologue of thioformaldehyde (1H212C32S). All reliable experimental transitions from publications over the last 42 years have been extracted and compiled into a consistent dataset with unique quantum number labelling and measurement uncertainties. The dataset covers the ground, ν1, ν2, ν3, ν4, ν5, ν6, and 2ν2 vibrational bands of H2CS. The ν4 and ν6 modes have very close band centres and consequently different data sources had incompatible vibrational assignments. Variational calculations are used as a basis to assign vibrational states of the associated transitions consistently. The transitions could then be processed using the robust MARVEL (Measured Active Rotational-Vibrational Energy Levels) procedure to produce a highly accurate set of 4254 rotation-vibration energy levels up to J=54 and 3729cm−1. The resulting set of labelled empirical-quality energies will be of significant use in the production of a hot molecular line list of H2CS, as well as other spectroscopic and radiative applications given the astrophysical importance of thioformaldehyde.