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.