Role of non-statistical effects in deciding the fate of HO3˙ in the atmosphere

Abstract

HO₃˙ has been postulated as a reservoir for OH˙ in various atmospheric reactions. Under collision-free conditions, experiments indicate that the lifetime of this species should be more than one microsecond. Interestingly, the binding energy of HO₃˙ is estimated to be ∼3 kcal mol⁻¹ by recent experimental as well as theoretical works. The value of the binding energy suggests that the lifetime of HO₃˙ should be in the picosecond range, and with this lifetime, HO₃˙ cannot act as a reservoir for OH˙. In the present work, using on-the-fly semiclassical dynamics, we argue that if non-RRKM effects are included, the lifetime of HO₃˙ may be higher than that estimated from the binding energy.