Mechanisms of production and death of singlet oxygen and ozone in fast-flow O/O<sub>2</sub>/N<sub>2</sub> gas mixtures

The experimental results of measurements of concentrations of O2(a1Δg) and O2(b1Σg+) in a fast-flow gas system with no plasma-chemical processes involving electrons and ions are described using a numerical spatially two-dimensional model. The dependences of O2(a1Δg) and O2(b1Σg+) concentration profiles on the gas pressure, the fraction of O atoms in O/N2 mixtures, and O2 additions to the gas mixture are obtained. The need to take into account the detailed vibrational kinetics of ozone and the processes of its formation on the tube surface in the model is shown. The treatment of the reaction of three-body recombination of O atoms on M = N2, O2 taking into account the reverse dissociation reaction of the formed highly excited molecule is proposed, and the functional dependence of the resulting coefficient krec(T)—the rate of three-body recombination is obtained, which agrees well with the measured temperature dependences krec(T). The channels of further relaxation of the formed excited molecules and oxygen atoms are obtained.