Reactions of HO2 with NO, OH and HO2 studied by EPR/LMR spectroscopy

A combined EPR/LMR spectrometer and fast-flow system has been used to investigate the reactions HO2 + NO(k1), HO2 + OH(k2), HO2 + HO2(k3) at room temperature. The rate constants have been measured: k1 = (7.0 ± 0.6) × 10−12 cm3 s−1 (P = 7–10 Torr);k2 = (5.2 ± 1.2) × 10−11 cm3 s−1 (P = 8–10 Torr);k3 = (1.65 ± 0.3) × 10−12 cm3 s−1 (P = 2.1–24.9 Torr). The conclusion is drawn from analysis of the literature and the present work that k2 and k3 do not depend on pressure up to 1 atm.