Ab Initio Study of Glycine Formation in the Condensed Phase: Carbon Monoxide, Formaldimine, and Water Are Enough
[ 1 ] Instytut Informatyki, Wydział Informatyki i Telekomunikacji, Politechnika Poznańska | [ P ] employee
2023
scientific article
english
- Pre-biotic astrochemistry
- Interstellar medium
- Molecular reactions
- Astrobiology
- Interstellar molecules
EN Glycine is considered being crucial in the formation of proteins and prebiotic substances. Nevertheless, the mechanism of spontaneous glycine formation under prebiotic Earth conditions or within the interstellar medium (ISM) remains a topic of debate, given the changing geochemical environment over Earth's history and its difficulty to detect it within the ISM. Yet, it is believed its formation could be possible in interstellar water-rich ice. In this study, using molecular dynamics (MD) simulations at the ab initio level of theory, enhanced with modern free energy calculations, we modelled the chemical reaction between carbon monoxide, formaldimine, and water to produce glycine. We estimated under what conditions, in condensed phase at 50K, 70K, 100K, and 300K, glycine is formed. We also explored the effect of different electric fields on this process. Our results show that glycine could be formed with energy barriers as low as 0.5 kcal/mol at 50K. We discuss whether this reaction could be a suitable candidate for explaining the mechanism of glycine formation under conditions that resemble various astrophysical environments such as planets, exoplanets, and Earth. This study is relevant to find a consensus between various proposals for the glycine formation. Moreover, it highlights the importance of metadynamics and Car–Parrinello MD methods as tools in finding unknown complex, multistep reaction mechanism pathways, possibly important to the astronomical phenomena.
956 - 975
CC BY (attribution alone)
czasopismo hybrydowe
final published version
at the time of publication
140
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