The influence of a single water molecule on the reaction of BrO + HO.

The influence of a single water molecule on the BrO + HO hydrogen extraction reaction has been explored by taking advantage of CCSD(T)/aug-cc-pVTZ//B3LYP/6-311 +  + G(d,p) method. The reaction in the absence of water have two distinct kinds of H-extraction channels to generate HOBr + O (Δ) and HBr + O, and the channel of generation of HOBr + O (Δ) dominated the BrO + HO reaction. The rate coefficient of the most feasible channel for the BrO + HO reaction in the absence of water is estimated to be 1.44 × 10 cm molecule s at 298.15 K, which is consistent with the experiment. The introduction of water made the reaction more complex, but the products are unchanged. Four distinct channels, beginning with HOHO with BrO, HOHO with BrO, BrOHO with HO, HOBrO with HO are researched. The most feasible channels, stemming from HOHO with BrO, and BrOHO with HO, are much slower than the reaction of BrO + HO without water, respectively. Thus, the existence of water molecule takes a negative catalytic role for BrO + HO reaction.