Charge transfer to hydrogen halide and halogen molecules from atomic and diatomic ions

Abstract

The change transfer from Xe +, Kr +, and Ar + to HI, HBr, HCl, Br 2, and Cl 2 and from O 2 + and N 2 + to HI, HBr, and HCl have been investigated. None of these reactant pairs undergoes a fast charge-transfer reaction. The probability of charge transfer for a given ion-molecule pair depends on the existence of a matching between the recombination energy of the reactant ion and an energy level of the product ion. No effect of Franck-Condon factors on the probability of charge transfer could be inferred from these results. The Kr +, Ar +, and N 2 + ions also undergo the alternate reaction, M + + HX → MH + + X, with the hydrogen halides, in competition with charge transfer. Except when charge transfer is favorable, the rate of this reaction is proportional to the reaction exothermicity. A few preliminary results on the reactions of Xe 2+, Kr 2+, and Ar 2+ ions with hydrogen halides and halogens are also reported.