Our automated reaction discovery program, AutoMeKin, has been utilized to investigate the formation of glycolonitrile (HOCH2CN) in the gas phase under the low temperatures of the interstellar medium (ISM). The feasibility of a proposed pathway depends on the absence of barriers above the energy of reactants and the availability of the suggested precursors in the ISM. Based on these criteria, several radical-radical reactions and a radical-molecule reaction have been identified as viable formation routes in the ISM. Among the radical-radical reactions, OH+CH2CN appears to be the most relevant, considering the energy of the radicals and its ability to produce glycolonitrile in a single step. However, our analysis reveals that this reaction produces hydrogen isocyanide (HNC) and formaldehyde (CH2O), with rate coefficients ranging from (7.3-11.5)×10−10 cm3 molecule−1 s−1 across the temperature range of 10-150 K. This finding is particularly interesing given the persistently unexplained overabundance of hydrogen isocyanide in the ISM. Among the radical-molecule reactions investigated, the most promising one is OH+CH2CNH, which forms glycolonitrile and atomic hydrogen with rate coefficients in the range (0.3-6.6)×10−10 cm3 molecule−1 s−1 within the 10-150 K temperature range. Our calculations indicate that the formation of both hydrogen isocyanide and glycolonitrile is efficient under the harsh conditions of the ISM.
@article{arxiv.2305.14899,
title = {Gas-phase formation of glycolonitrile in the interstellar medium},
author = {Luis Guerrero-Mendez and Anxo Lema-Saavedra and Elena Jimenez and Antonio Fernandez-Ramos and Emilio Martinez-Nunez},
journal= {arXiv preprint arXiv:2305.14899},
year = {2023}
}