Exploring the reaction channels between arsine and the hydroxyl radical

2017-05-05T16:38:17Z (GMT) by Rommel B. Viana
<p>The aim of this study was to present the reaction mechanism channels between arsine (AsH<sub>3</sub>) and hydroxyl (OH) which was evaluated at CCSD(T)/CBS//CCSD/cc-pVTZ level. One potential channel is the hydrogen abstraction pathway (R1), leading to AsH<sub>2</sub> and H<sub>2</sub>O products, which occurs due to the formation of an entrance complex (AsH<sub>3</sub>OH) followed by a 1,2-hydrogen shift pathway (involving the proton transfer from the arsine group to hydroxyls, with one leading to the products). Additional channels are accessed via H-elimination pathways of the entrance complexes, forming arsinous acid (AsH<sub>2</sub>OH; R2) and arsine oxide (AsH<sub>3</sub>O; R3). In this respect, R2 is the only exoergic route of the three exit channels, representing the major branching ratio at 200–1000 K and, after 2000 K, R1 increases gradually becoming the major route of this reaction. In contrast, even at 4000 K, R3 is a highly unfeasible pathway. Therefore, the information predicted here provides new insights into the neutral–neutral chemical reaction dynamics regarding the Group V hydrides. On the other side, the R2 pathway may have some potential to solve the arsine oxidation puzzle as a possible primary pathway to the arsenic-oxygen species formation.</p>