open access

https://hdl.handle.net/2115/63550

Hydrogen-deuterium substitution in solid ethanol by surface reactions at low temperatures

英語

ISM: molecules

2016-07-18

Oxford University Press

Monthly notices of the royal astronomical society

462(1)

689-695

Ethanol (CH3CH2OH) is one of the most abundant complex organic molecules in star-forming regions. Despite its detection in the gas phase only, ethanol is believed to be formed by low temperature grain-surface reactions. Methanol, the simplest alcohol, has been a target for observational, experimental, and theoretical studies in view of its deuterium enrichment in the interstellar medium; however, the deuterium chemistry of ethanol has not yet been an area of focus. Recently, deuterated dimethyl ether, a structural isomer of ethanol, was found in star forming regions, indicating that deuterated ethanol can also be present in those environments. In this study, we performed laboratory experiments on the deuterium fractionation of solid ethanol at low temperatures through a reaction with deuterium (D) atoms at 10 K. Hydrogen (II)-D substitution, which increases the deuteration level, was found to occur on the ethyl group but not on the hydroxyl group. In addition, when deuterated ethanol (e.g. CD3CD2OD) solid was exposed to H atoms at 10 K, D-H substitution that reduced the deuteration level occurred on the ethyl group. Based on the results, it is likely that deuterated ethanol is present even under H-atom-dominant conditions in the interstellar medium.

学術雑誌論文

Version of Record

This article has been accepted for publication in　Monthly notices of the royal astronomical society, © 2016,Oba, Yasuhiro; Osaka, Kazuya; Chigai, Takeshi; Kouchi, Akira; Watanabe, Naoki, Published by Oxford University Press on behalf of The Royal Astronomical Society. All rights reserved.

0035-8711