Ab initio studies of ClOx reactions. I. Kinetics and mechanism for the OH+ClO reaction

The reaction of OH with ClO has been investigated by ab initio molecular orbital and variational transition state theory calculations. Both singlet and triplet potential energy surfaces predicted by the G2M method are presented. The reaction was shown to take place primarily over the singlet surface by two main channels producing HO2+Cl and HCl+O2(1Δ), with the former being dominant. The predicted total rate constant, kt=5.27×10−9 T1.03 exp (−40/T) cm3 molecule−1 s−1, and product branching ratios in the temperature range 200–500 K at P