Hydrogen abstraction reactions in formic and thioformic acid isomers by hydrogen and deuterium atoms. Insights on isomerism and deuteration

TL;DR

This study investigates hydrogen abstraction reactions affecting isomerism and deuteration of formic and thioformic acids on interstellar dust grains, providing insights into molecular processes in space.

Contribution

It offers new insights into the mechanisms of isomerization and deuteration of formic and thioformic acids on dust grains at low temperatures.

Findings

Reactions can induce isomerization on dust grains.

Deuterium enrichment occurs via similar abstraction mechanisms.

Results help explain molecular diversity in interstellar space.

Abstract

The isomerism of molecules in the interstellar medium and the mechanisms behind it are essential questions in the chemistry of organic molecules in space. In particular, for the simple formic and thioformic acids, the low temperatures found in molecular clouds indicate that cis-trans isomerization in the gas-phase must be impeded. Reactions happening on top of interstellar dust grains may explain the isomer interconversion at low temperatures. We studied the isomerization processes of formic and thioformic acid susceptible to happen on the surface of interstellar dust grains and initiated by H abstraction reactions. Similarly, deuterium enrichment of the acids can occur by the same mechanism. Our objective is to shed light on both topics to increase our understanding of key precursors of organic molecules in space.