HO2˙ as a potential reactant for the bimolecular reaction of tert-butoxy radicals in the atmosphere

Abstract

Alkoxy radicals are key intermediates in the atmospheric degradation of volatile organic compounds. For most alkoxy radicals, reaction with O₂ is the primary loss mechanism; however, only α-hydrogen-bearing alkoxy radicals undergo a reaction with O₂. Interestingly, if one considers an alkoxy radical that does not possess an α-hydrogen, reaction with O₂ is unlikely. In the present work, we propose HO₂˙ as a potential reactant for such alkoxy radicals. We have considered the tert-butoxy radical (tBuO˙) as a prototype for those alkoxy radicals that do not possess an α-hydrogen. By means of high-level quantum chemical calculations, we have studied the energetics of the tBuO˙ + HO₂˙ reaction along with isomerization and decomposition pathways. Finally, we have discussed the possible atmospheric implications of all three paths in the atmosphere using reaction rate calculations.