Theoretical studies of the reactions of O(3P) with halogenated methyl (I)

The reaction of o(³P) with CH₂C1 radical has been studied usingab initio molecular orbital theory. G2 (MP.2) method is used to calculate the geometrical parameters, vibrational frequencies and energies of various stationary points on the potential energy surface. The reaction mechanism is revealed. The addition of o(³P) with CH₂Cl leads to the formation of an energy rich intermediate OCH₂Cl^* which can subsequently undergo decomposition or isomerization to the final products. The calculated heat of reaction for each channel is in agreement with the experimental value. The production of H+CHClO and C1+CH₂O are predicted to be the major channels. The overall rate constants are calculated using transition state theory on the basis ofab initio data. The rate constant is pressure independent and exhibits negative temperature dependence at lower temperatures, in accordance with the experimental results.