Temperature Dependences of the Rate Coefficients for the Reactions of Ar+ with O2, H2, and D2

Abstract

A series of measurements have been made using the flowing afterglow technique to investigate the temperature dependence of the rate coefficients for the reactions of Ar⁺ with O₂, H₂, and D₂ in the temperature range 80–560°K. The rate coefficient for the reaction of Ar⁺ with O₂ has been found to decrease with increasing temperature approximately as T^−0.5. In contrast, the rate coefficients for the reactions of Ar⁺ with H₂ and D₂ increased with increasing temperature, and the rate coefficients for the reactions ArH⁺ + H₂ and ArD⁺ + D₂ were independent of temperature within experimental error. The rate coefficient for the reaction of Ar⁺ with N₂ was measured at 280°K and found to be dependent on the Ar number density.