Production of the Atmospheric Oxidant Radicals OH and HO2 from the Ozonolysis of Alkenes

Abstract

The reactions of ozone with alkenes are of importance within atmospheric chemistry as a non-photolytic source of the oxidant radicals OH, HO2 and RO2. While OH yields are relatively well constrained, few data exist for production of HO2 or RO2. We report direct measurements of total radical yields from a range of small (C2-C5) alkenes, using LIF and PERCA techniques within large simulation chamber experiments. OH yields are found to be consistent with established understanding, while HO2 yields are substantially smaller than previous measurements suggest, but in good agreement with those assumed within current atmospheric chemical mechanisms. © Springer Science+Business Media Dordrecht 2013.