Theoretical kinetic study of two competing paths in the H2O2 + O(3P) → HO2 + OH reaction

Ab initio-TST calculations were carried out to study the kinetics of the title reaction. The H atom and the OH abstraction paths leading to the same products HO2 and OH have been considered. The ZPE and BSSE corrected classical barrier heights were predicted to be 7.4 and 17.3 kcal/mol, respectively. Calculated thermal rate constants over the temperature range 300-5000 K showed that the H-abstraction path was the most likely to occur for temperatures below 2500 K which confirms the result found in a previous study [Y. Tarchouna, M. Bahri, N. Jaïdane, Z. Ben Lakdar, J. Mol. Struct. (Theochem), 189 (2003) 664]. The contribution of OH abstraction path to the reaction was predicted to be important for high temperatures.