Reactions of HO2 studied by flash photolysis with diode-laser spectroscopy
Abstract
Tunable diode lasers make it possible to record the infrared spectra of transient species at Doppler-limited resolution on time-scales of <1 ms. This technique has been combined with flash photolysis to study reactions of the HO2 radical. Studies of the recombination of HO2 radicals at total pressures between 7 and 20 Torr give rate coefficients in the range (1.5–2.0) x 10–12 cm3 s–1 at 305 K for oxygen carriers. These values are significantly lower than other workers have found near atmospheric pressure. They support the view that this reaction yields H2O2+ O2 by two parallel paths, one a direct disproportionation the other involving an H2O4 intermediate.