Please use this identifier to cite or link to this item: http://hdl.handle.net/10995/117792
Title: Methoxymethanol formation starting from CO hydrogenation
Authors: He, J.
Simons, M.
Fedoseev, G.
Chuang, K. -J.
Qasim, D.
Lamberts, T.
Ioppolo, S.
Mcguire, B. A.
Cuppen, H.
Linnartz, H.
Issue Date: 2022
Publisher: EDP Sciences
Citation: Methoxymethanol formation starting from CO hydrogenation / J. He, M. Simons, G. Fedoseev et al. // Astronomy and Astrophysics. — 2022. — Vol. 659. — A65.
Abstract: Context. Methoxymethanol (CH3OCH2OH) has been identified through gas-phase signatures in both high- and low-mass star-forming regions. Like several other C-, O-, and H-containing complex organic molecules (COMs), this molecule is expected to form upon hydrogen addition and abstraction reactions in CO-rich ice through radical recombination of CO hydrogenation products. Aims. The goal of this work is to experimentally and theoretically investigate the most likely solid-state methoxymethanol reaction channel athe recombination of CH2OH and CH3O radicals afor dark interstellar cloud conditions and to compare the formation efficiency with that of other species that were shown to form along the CO-hydrogenation line. We also investigate an alternative hydrogenation channel starting from methyl formate. Methods. Hydrogen atoms and CO or H2CO molecules were co-deposited on top of predeposited H2O ice to mimic the conditions associated with the beginning of arapida CO freeze-out. The formation of simple species was monitored in situ using infrared spectroscopy. Quadrupole mass spectrometry was used to analyze the gas-phase COM composition following a temperature-programmed desorption. Monte Carlo simulations were used for an astrochemical model comparing the methoxymethanol formation efficiency with that of other COMs. Results. The laboratory identification of methoxymethanol is found to be challenging, in part because of diagnostic limitations, but possibly also because of low formation efficiencies. Nevertheless, unambiguous detection of newly formed methoxymethanol has been possible in both CO+H and H2CO+H experiments. The resulting abundance of methoxymethanol with respect to CH3OH is about 0.05, which is about six times lower than the value observed toward NGC 6334I and about three times lower than the value reported for IRAS 16293B. Astrochemical simulations predict a similar value for the methoxymethanol abundance with respect to CH3OH, with values ranging between 0.03 and 0.06. Conclusions. We find that methoxymethanol is formed by co-deposition of CO and H2CO with H atoms through the recombination of CH2OH and CH3O radicals. In both the experimental and modeling studies, it is found that the efficiency of this channel alone is not sufficient to explain the observed abundance of methoxymethanol with respect to methanol. The rate of a proposed alternative channel, the direct hydrogenation of methyl formate, is found to be even less efficient. These results suggest that our knowledge of the reaction network is incomplete or involving alternative solid-state or gas-phase formation mechanisms. ©
Keywords: ASTROCHEMISTRY
ISM: MOLECULES
MOLECULAR PROCESSES
SOLID STATE: VOLATILE
ATOMS
DEPOSITION
EFFICIENCY
GASES
INFRARED SPECTROSCOPY
INTELLIGENT SYSTEMS
MASS SPECTROMETRY
MOLECULES
MONTE CARLO METHODS
TEMPERATURE PROGRAMMED DESORPTION
ASTROCHEMISTRY
CO HYDROGENATION
COMPLEX ORGANIC MOLECULES
CONDITION
GAS-PHASES
ISM:MOLECULES
METHYL FORMATE
MOLECULAR PROCESS
PHASE SIGNATURE
SOLID STATE: VOLATILE
HYDROGENATION
URI: http://hdl.handle.net/10995/117792
Access: info:eu-repo/semantics/openAccess
SCOPUS ID: 85126762478
ISSN: 46361
DOI: 10.1051/0004-6361/202142414
metadata.dc.description.sponsorship: FEUZ-2020-0038; Horizon 2020 Framework Programme, H2020; Royal Society; European Research Council, ERC; Nederlandse Organisatie voor Wetenschappelijk Onderzoek, NWO
Acknowledgements. This work has been financially supported through an NWO grant within the framework of the Dutch Astrochemistry Network II. We thank Julie Korsmeyer for her technical assistance. J.H. is involved in research that is supported through the European Research Council under the Horizon 2020 Framework Program via the ERC Advanced Grant Origins 83 24 28. G.F. acknowledges financial support from the Russian Ministry of Science and Higher Education via the State Assignment Contract. FEUZ-2020-0038. S.I. acknowledges support from the Royal Society.
Appears in Collections:Научные публикации, проиндексированные в SCOPUS и WoS CC

Files in This Item:
File Description SizeFormat 
2-s2.0-85126762478.pdf3,81 MBAdobe PDFView/Open


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.