The formation of isomers of C2H2O—ketene (H2CCO), ethynol (HCCOH), and oxirene (c-CHCHO)—was investigated in interstellar ice analogs composed of carbon monoxide and water. Using tunable photoionization time-of-flight mass spectrometry to selectively ionize the isomer of interest, ketene and ethynol were detected as reaction products, but oxirene remains elusive. These findings demonstrate that organic compounds that are precursors to complex organic molecules can form without an organic source of carbon. Furthermore, we report the first plausible detection of ethynol in astrophysically relevant ices. These investigations were supported by theoretical calculations describing reaction energies, pathways, ionization energies, and harmonic frequencies.
The formation of complex organic molecules by energetic electrons mimicking secondary electrons generated within trajectories of galactic cosmic rays was investigated in interstellar ice analog samples of carbon monoxide and water at 5 K. Simulating the transition from cold molecular clouds to star-forming regions, newly formed products sublimed during the temperature-programmed desorption and were detected utilizing isomer-specific photoionization reflectron time-of-flight mass spectrometry. Using isotopically labeled ices, tunable photoionization, and adiabatic ionization energies to discriminate between isomers, isomers up to C 2 H 4 O 2 and C 2 H 6 O 2 were identified, while non-isomer-specific findings confirmed complex organics with molecular formulas up to C 4 H 6 O 4 . The results provide important constraints on reaction pathways from simple inorganic precursors to complex organic molecules that have both astrochemical and astrobiological significance.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.