A computational journey in the CH₂O₂S land: an accurate rotational and ro-vibrational analysis of the sulfene molecule and the O,S- and O,O-monothiocarbonic acids

Abstract

Molecules containing sulfur play an important role in atmospheric chemistry, but their reactivity in such environment is far from being well characterised. Therefore, important transient species might still have to be disclosed. In this regard, this paper aims at contributing to this field by means of the computational spectroscopic characterisation of potentially relevant atmospheric species, such as the ${\mathrm{CH}}_2{\mathrm{O}}_2\mathrm{S}$ isomers. Based on our computational investigation, the most stable species are the carbonothionic O,S- and O,O-acids. In addition to them, the sulfene molecule has also been considered. For all these species, the equilibrium structure and the corresponding rotational constants have been accurately evaluated using a coupled-cluster-based composite approach. All the other parameters required for the simulation of the rotational and ro-vibrational spectra have been obtained by exploiting density functional theory.

GRAPHICAL ABSTRACT

Keywords:

• Spectroscopic characterisation
• ab initio methods
• atmospheric chemistry
• sulfur-containing compounds
• computational spectroscopy

Acknowledgments

The authors thank Dr. Mattia Melosso for the useful discussions.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This study was supported by Bologna University (RFO funds) and by Ministero dell'Istruzione, dell'Universitá e della Ricerca (MIUR) (Project PRIN 2015, Grant Number 2015F59J3R).