A study of the isoenergetic reaction H+3+O2 ? O2H++H2

Abstract

The isoenergetic reaction H+ 3+O2 ? O2H++H2 has been studied in a flowing afterglow and a flow‐drift tube. In the former, the equilibrium constant was found to be 1.8±0.5. In the latter, the forward and reverse rate constants were measured separately and, at near‐thermal energies, were 7×10−10 and 3×10−10 cm3/sec, respectively. These values are in good agreement with recent ion‐cyclotron‐resonance (ICR) studies of this reaction. The flow‐drift tube study found the forward and reverse rate constants to be virtually energy independent, attesting to the isoenergeticity of this reaction. As a further comparison with the ICR measurements, the rate constant for the reaction H+ 3+N2 → N2H++H2 was measured as a function of relative kinetic energy. At near‐thermal energies, k=2×10−9 cm3/sec, in excellent agreement with the ICR value.