Representative structures of six S-bearing products identified in experiments with C2H2 + H2S + H. These are presented for visualization purposes and do not depict the exact minimum energy geometries of the species generated in the experiments. – astro-ph.GA
The chemical network governing interstellar sulfur has been a topic of unrelenting debate over the past decades because of the apparent discrepancy between its expected and observed abundances in different interstellar environments.
More recently, astronomical observations of CH3Ch2SH and CH2CS highlighted the importance of galaxy formation pathways for two-carbon sulfur-bearing organic molecules. In this work, we perform a laboratory investigation of the solid-state chemistry resulting from interactions between C2H2 molecules and SH radicals – both of which are thought to exist in interstellar ices – at 10 K.
Reflectance absorption infrared spectroscopy and quadrupole mass spectrometry are used as analytical techniques in conjunction with temperature-programmed desorption experiments. We confirm that SH radicals can initiate the sulfur reaction network under interstellar cloud conditions and identify at least six sulfur products: CH3Ch2SH, CH2CHSH, HSCH2Ch2SH, H2S2and temporarily CH3CHS and CH2In addition to CS, we use computational calculations to identify the reaction pathways that play a role in the chemical network behind our experimental results.
CH is the major sulfur-bearing organic molecule formed under our experimental conditions3Ch2SH and its formation yields increase with ratios of H to other reactants. It acts as a sink for the sulfur budget within the network, which is formed at the expense of other unsaturated substances. The astrophysical implications of the proposed chemical network are discussed here.
Julia C. Santos, Joan Enrique-Romero, Tanja Lamberts, Harold Linnards, Ko-Ju Chuang
Comments: 9 figures, 2 pages, accepted for publication July 5, 2024 in ACS Earth and Space Chemistry
Subjects: Astrophysics of Galaxies (astro-ph.GA); Solar and Stellar Astrophysics (astro-ph.SR)
Citation: arXiv:2407.09730 [astro-ph.GA] (or arXiv:2407.09730v1 [astro-ph.GA] for this version)
https://doi.org/10.48550/arXiv.2407.09730
Pay attention to know more
Corresponding DOI:
https://doi.org/10.1021/acsearthspacechem.4c00150
Pay attention to know more
Submission history
Posted by: Julia C. Santos
[v1] Sat, 13 Jul 2024 00:28:00 UTC (440 KB)
https://arxiv.org/abs/2407.09730
Astronomy, Astrophysics,
