Flowing Afterglow Studies of the Reactions of the Rare-Gas Molecular Ions He2+, Ne2+, and Ar2+ with Molecules and Rare-Gas Atoms

Abstract

The flowing afterglow technique has been used to measure rate coefficients and product channels for the reactions of He₂⁺, Ne₂⁺, and Ar₂⁺ with the rare‐gas atoms Ne, Ar, and Kr, and with the molecules NO, O₂, CO, N₂, and CO₂ at 200°K. These reactions are found to proceed principally by asymmetric charge transfer. The experimental results for the reactions of the rare‐gas molecular ions with rare‐gas atoms indicate a correlation between reaction probability and reaction exoergicity analogous to that observed for asymmetric atomic ion–atomic neutral charge‐transfer reactions. The reactions with molecules are found to proceed with unit reaction probability with the exception of the reactions Ar₂⁺+O₂ and Ar₂⁺+NO. The reaction probability for the reactions of the molecular rare‐gas ions with molecules is not very sensitive to an energy resonance criterion. Finally, rate coefficients and reaction channels for the reaction of the mixed rare‐gas molecular ions HeNe⁺, ArKr⁺, and ArCO⁺ with Ne, Kr, and CO, respectively, are reported.