AUTHOR=Ferus Martin , Knížek Antonín , Petera Lukáš , Pastorek Adam , Hrnčířová Jana , Jankovič Luboš , Ivanek Ondřej , Šponer Jiří , Křivková Anna , Saeidfirozeh Homa , Civiš Svatopluk , Chatzitheodoridis Elias , Mráziková Klaudia , Nejdl Lukáš , Saija Franz , Šponer Judit E. , Cassone Giuseppe TITLE=Formamide-Based Post-impact Thermal Prebiotic Synthesis in Simulated Craters: Intermediates, Products and Mechanism JOURNAL=Frontiers in Astronomy and Space Sciences VOLUME=Volume 9 - 2022 YEAR=2022 URL=https://www.frontiersin.org/journals/astronomy-and-space-sciences/articles/10.3389/fspas.2022.882145 DOI=10.3389/fspas.2022.882145 ISSN=2296-987X ABSTRACT=

Influx of matter from impacting meteoroids and hydrothermal crater weathering are important factors modifying the rock and mineral inventory of young planets undergoing heavy bombardment. These processes may have influenced not only the geochemical environment of, e.g., early Mars and other planets, but also the peculiar prebiotic chemistry on early Earth. Here, we present a synergistic experimental and computational investigation of the intermediates of chemical reactions of the formamide-based synthesis of canonical and non-canonical nucleobases by thermochemistry in hot hydrothermal crater environments. We put our findings into context with previously investigated plasma-initiated synthesis occuring directly during impact. Both processes result into the formation of all canonical nucleobases, hypoxanthine, purine, and into the onset of the simplest amino acid glycine. Furthermore, it turns out that radical species such as CN and H play a key role in the plasma-assisted impact chemistry. However, post-impact thermochemistry is essential for the origin of formamidine and 2-aminoacetonitrile, intermediate species detected in this study by means of FTIR spectroscopy.