title: Theoretical study of the mechanisms and kinetics of the reactions of hydroperoxy (HO2) radicals with hydroxymethylperoxy (HOCH2O2) and methoxymethylperoxy (CH3OCH2O2) radicals.
abstract: The reactions of hydroperoxy radicals with hydroxymethylperoxy and methoxymethylperoxy radicals were studied using the hybrid density functional theory and the coupled-cluster theory with complete basis set extrapolation. In contrast with the unsubstituted alkylperoxy reactions, it was found that OH-substitution has a significant effect on the reaction mechanism. Several hydrogen bonding reaction precursors exist at the start of the reaction. The reaction pathways show a strongly anisotropic character. The preferred transition states are four-, five-, six-, or seven-membered cyclic structures. The predicted rate coefficients are expressed as k(T) = 8.48 × 10(-24)T(3.55)e(2164/T) + 2.37 × 10(-29)T(4.70)e(3954/T) cm(3) molecule(-1) s(-1). Based on the available experimental data in the temperature range 275-333 K, the theoretical and experimental results are in agreement with a relative average deviation of only 8%. The nascent products at low and high temperatures are hydroperoxide molecules and hydroxyl radicals, respectively. A potential source has been found for the production of formic acid and new insights into the experimental observations are presented.
authors.affiliation: College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, People's Republic of China. baoshan@whu.edu.cn.
authors.forename: Youxiang
authors.initials: Y
authors.lastname: Shao
authors.forename: Hua
authors.initials: H
authors.lastname: Hou
authors.forename: Baoshan
authors.initials: B
authors.lastname: Wang