Electronic transitions in the ion-molecule reaction (Ar+ + H2→Ar + H2+)→ArH+ + H

Abstract

A collinear reactive study of the ion-molecule system (Ar + ${\mathrm{H}}_2^{+}$, ${\mathrm{Ar}}^{+}$ + ${\mathrm{H}}_2$, Ar${\mathrm{H}}^{+}$ + H) is presented. The main emphasis was directed towards the two reactions ${\mathrm{Ar}}^{+}+{\mathrm{H}}_2(\nu =0)\to \mathrm{Ar}{\mathrm{H}}^{+}+\mathrm{H}$ and $\mathrm{Ar}+{{\mathrm{H}}_2}^{+}({\nu }^{\prime }=2)\to \mathrm{Ar}{\mathrm{H}}^{+}+\mathrm{H}$, which exhibit avoided-crossing features. It is shown that reactive transition probabilities obtained from an exact collinear treatment which incorporated a large number of vibrational states to ensure convergence are reproduced by simple reactive curve-crossing models.