Kinetics of the reaction of HO2 with ozone

Publisher Website
Google Scholar
Abstract
Rate constants were measured for the reaction HO2+O3→OH+2O2(k 1) using a discharge‐flow system with laser magnetic resonance detection of both HO2 and OH. k 1 was determined directly from the first order decay of HO2 in excess O3 when C2F3Cl was added to scavenge the OH product and prevent interference from the faster reaction OH+O3→HO2+O2(k 2). The ratio k 2/k 1 was independently determined from the steady‐state [HO2]/[OH] ratio obtained without C2F3Cl. Results from the scavenger method are given by k 1= (1.4±0.4)×10−14 exp [−(580±100)/T] cm3 s−1 for 245 K<T<365K. Results of the ratio measurements are in good agreement with these data when combined with a directly measured value of k 2?1.0)×10−14 cm3 s−1 at 300 K. These measurements are compared with other studies and some implications for stratosphericozone chemistry are discussed.