Reactions of CH2(X̃ 3B1) and CH2(ã 1A1) with O2 studied by time-resolved FTIR spectroscopy

Electronic state-specific CH2 reactions with O2 in the gas phase were investigated by time-resolved Fourier transform infrared emission spectroscopy. CH2(X̃3B1) and CH2(ã 1A1) radicals were produced by laser photolysis of ketene at 351 and 308 nm, respectively. Vibrationally excited products of CO(v⩽10), CO2(ν3, v⩽7), H2CO(ν1) and H2O(ν3) formed in the CH2(X̃ 3B1)+O2 reaction and CO(v⩽10), CO2(ν3, v⩽8), H2CO(ν1) formed in the CH2(ã 1A1)+O2 reaction have been observed. For each reaction, three possible channels have been verified.