The photolysis of bis(fluoroxy)difluoromethane (CF 2(OF) 2) and its photochemical reaction with carbon monoxide

Abstract

The photochemical decomposition of bis(fluoroxy)difluoromethane (CF 2(OF) 2) and its reaction with CO at 253.7 nm was studied in a static system at temperatures between −20 and 30 °C. At low conversion the decomposition of pure CF 2(OF) 2 proceeds according to the reaction stoichiometry CF 2(OF) 2 = CF 2O + F 2 + 1 2 O 2 with a quantum efficiency φ of 0.65 ± 0.03 molecules quantum −1 independent of the experimental conditions. The addition of a sufficiently large concentration of CF 2O produces a change in the reaction mechanism and trifluoromethyl peroxide (CF 3O) 2 is observed among the reaction products. An increase in the oxygen pressure tends to increase the quantum efficiency to an upper limit of 1 molecule quantum −1. In the presence of CO the reaction stoichiometry is CF 2(OF) 2 + 2CO → 2CF 2O + CO 2 ‡ n = O and φ = 1.0 ± 0.1 molecules quantum −1 for all experimental conditions. The addition of oxygen changes the reaction mechanism, and a decrease in the total pressure accompanied by the formation of bis(monofluorocarbonyl)-peroxide (FCO) 2O 2 was observed.