Kinetics of the Reaction HOCO + O2 in the Gas Phase

Using the discharge flow method, the kinetics of the gas phase reaction HOCO + O2 products (1) was investigated at room temperature and pressures around p ≈ 2.0 mbar with Far Infrared Laser Magnetic Resonance (FIR-LMR) detection of HOCO, HO2 , and OH. From the measured concentration- versus-time decay profiles of HOCO in the absence and presence of a large excess of O2 , the overall rate constant of the reaction was found to be k1 (296 K) = (9.9 ±1.5) • 1011 cm3/mol • s. The main reaction channel, which leads to production of HO2 + CO2 , could be established.