Anharmonic fundamental vibrational frequencies and spectroscopic constants of the potential HSO2 radical astromolecule

The recent report that HSO2 is likely kinetically favored over the HOSO thermodynamic product in hydrogen addition to sulfur dioxide in simulated Venusian atmospheric conditions has led to the need for reference rotational, vibrational, and rovibrational spectral data for this molecule. While matrix-isolation spectroscopy has been able to produce vibrational frequencies for some of the vibrational modes, the full infrared to microwave spectrum of 1 (2)A ' HSO2 is yet to be generated. High-level quantum chemical computations show in this work that the >2.5 D dipole moment of this radical makes it a notable target for possible radioastronomical observation. Additionally, the high intensity antisymmetric S-O stretch is computed here to be 1298.3 cm(-1), a 13.9 cm(-1) blueshift up from H-2 matrix analysis. In any case, the full set of rotational and spectroscopic constants and anharmonic fundamental vibrational frequencies is provided in this work in order to help characterize HSO2 and probe its kinetic favorability.

Automated summary

The study investigates the molecular structure and spectroscopic properties of HSO2 under simulated Venusian atmospheric conditions, revealing its potential high dipole moment and intense antisymmetric S-O stretching frequency. The research findings provide important reference information for further understanding the kinetic properties of HSO2.