Proposed importance of HOCO chemistry: Inefficient formation of CO$_2$ from CO and OH reactions on ice dust

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Ishibashi, Atsuki, Molpeceres, Germán, Hidaka, Hiroshi, Oba, Yasuhiro, Lamberts, Thanja, Watanabe, Naoki
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866914980072259584
author Ishibashi, Atsuki
Molpeceres, Germán
Hidaka, Hiroshi
Oba, Yasuhiro
Lamberts, Thanja
Watanabe, Naoki
author_facet Ishibashi, Atsuki
Molpeceres, Germán
Hidaka, Hiroshi
Oba, Yasuhiro
Lamberts, Thanja
Watanabe, Naoki
contents With the advent of JWST ice observations, dedicated studies on the formation reactions of detected molecules are becoming increasingly important. One of the most interesting molecules in interstellar ice is CO$_2$. Despite its simplicity, the main formation reaction considered, CO + OH -> CO$_2$ + H through the energetic HOCO* intermediate on ice dust, is subject to uncertainty because it directly competes with the stabilization of HOCO as a final product which is formed through energy dissipation of HOCO* to the water ice. When energy dissipation to the surface is effective during reaction, HOCO can be a dominant product. In this study, we experimentally demonstrate that the major product of the reaction is indeed not CO$_2$, but rather the highly reactive radical HOCO. The HOCO radical can later evolve into CO$_2$ through H-abstraction reactions, but these reactions compete with addition reactions, leading to the formation of carboxylic acids (R-COOH). Our results highlight the importance of HOCO chemistry and encourage further exploration of the chemistry of this radical.
format Preprint
id arxiv_https___arxiv_org_abs_2410_01373
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Proposed importance of HOCO chemistry: Inefficient formation of CO$_2$ from CO and OH reactions on ice dust
Ishibashi, Atsuki
Molpeceres, Germán
Hidaka, Hiroshi
Oba, Yasuhiro
Lamberts, Thanja
Watanabe, Naoki
Astrophysics of Galaxies
With the advent of JWST ice observations, dedicated studies on the formation reactions of detected molecules are becoming increasingly important. One of the most interesting molecules in interstellar ice is CO$_2$. Despite its simplicity, the main formation reaction considered, CO + OH -> CO$_2$ + H through the energetic HOCO* intermediate on ice dust, is subject to uncertainty because it directly competes with the stabilization of HOCO as a final product which is formed through energy dissipation of HOCO* to the water ice. When energy dissipation to the surface is effective during reaction, HOCO can be a dominant product. In this study, we experimentally demonstrate that the major product of the reaction is indeed not CO$_2$, but rather the highly reactive radical HOCO. The HOCO radical can later evolve into CO$_2$ through H-abstraction reactions, but these reactions compete with addition reactions, leading to the formation of carboxylic acids (R-COOH). Our results highlight the importance of HOCO chemistry and encourage further exploration of the chemistry of this radical.
title Proposed importance of HOCO chemistry: Inefficient formation of CO$_2$ from CO and OH reactions on ice dust
topic Astrophysics of Galaxies
url https://arxiv.org/abs/2410.01373