Mechanisms of HO2(A2A') Excitation in Various Chemical Systems

Article abstract of DOI:10.1021/j100243a029

Chemiluminescence from electronically excited HO2 has been detected between 800 and 1200 nm in various gas-phase flow systems using a near-infrared-sensitive photomultiplier.The emission essentially consists of ν₃ sequences of the HO2(A²A' -> X²A ) transition.From spectroscopic and kinetic evidence it is concluded that, in addition to the previously suggested excitation of thermal HO2 by O2(¹Δ), at least two mechanisms are responsible for the formation of HO2(²A',ν₃'a mechanism involving the consecutive excitation of one HO2 molecule by two O2(¹Δ) molecules and (ii) the thermal recombination of H atoms with O2.