KINETICS AND PRODUCTS OF THE REACTIONS OF CH3O2 WITH CL AND CLO

The mechanisms of the reactions CH3O2 + Cl --> products (1) and CH3O2 + ClO --> products (2) have been studied at 298 K using a discharge no w reactor coupled to laser induced fluorescence for the detection of C H3O, observed as a product of both reactions, and mass spectrometry fo r the detection of other species. In the kinetic study of reaction (1) , the channel producing the Criegee radical, CH2O2, has been found to be preponderant compared to the CH3O forming channel : CH3O2 + Cl --> CH3O + ClO (1a), k(1a) = (2.0 +/- 0.4) x 10(-11) cm(3) molecule(-1) s( -1) and CH3O2 + Cl --> CH2O2 + HCl (1b), k(1b) = (2.0 +/- 0.4) x 10(-1 0) cm(3) molecule(-1) s(-1). The study of reaction (2) aimed at identi fying the reaction pathways : CH3O2 + ClO --> CH3O + ClOO (2a) and CH3 O2 + ClO --> CH3OCl + O-2 (2b). The branching ratio for the first chan nel has been determined : alpha(2a) = 0.3 + 0.1. These results are com pared with other recent literature data and their atmospheric implicat ion is briefly discussed.