Anharmonic Vibrational Spectrum and Experimental Matrix Isolation Study of Thioformic Acid Conformers -- Potential Candidates for Molecular Cloud and Solar System Observations?

Abstract

Thioformic acid (TFA) is the sulfur analog of formic acid, the simplest organic acid. It has three analogues HCOSH, HCSOH, and HCSSH, each of them having two rotational isomeric (rotameric) forms: trans and cis where the trans form is energetically more stable. In this article, we study computational energetics and anharmonic vibrational spectrum of TFA including overtone and combination vibrations. We also studied experimental photoisomerization and photodecomposition channels of HCOSH molecules with different wavelengths. We suggest that TFA is a potential sulfur containing candidate molecule for interstellar and planetary observations and discuss these in a light of different radiation environments in space. More generally, we discuss that infrared radiation driven photo-isomerization reactions may be a common phenomenon in such environments and can affect the chemical reaction pathways of organic and other interstellar molecules.

arXiv commentAccepted to ApJ, 21 pages, 4 figures

References in corpus (11)

• Photochemistry and astrochemistry: photochemical pathways to interstellar complex organic molecules
• On the reservoir of sulphur in dark clouds : chemistry and elemental abundance reconciled
• Complex organic molecules in the Galactic Centre: the N-bearing family
• Thiols in the ISM: first detection of HC(O)SH and confirmation of C${}_2$H${}_5$SH
• Photolytic Hazes in the Atmosphere of 51 Eri b
• A Uniform Contribution of Core-Collapse and Type Ia Supernovae to the Chemical Enrichment Pattern in the Outskirts of the Virgo Cluster
• Sulphur abundance in Galactic stars
• Chemical complexity induced by efficient ice evaporation in the Barnard 5 molecular cloud
• Trans-cis molecular photoswitching in interstellar Space
• From interstellar carbon monosulfide to methyl mercaptan: paths of least resistance
• Accurate millimetre and submillimetre rest frequencies for $cis$- and $trans$-dithioformic acid, HCSSH

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