Electron transfer between multicharged ions and neutral species

Abstract

A reduced coupling matrix-element formula has been developed for application to the class of reactions $A^{+z}+B\to A^{+z-1\mathrm{}}+B^{+}$, where $4\le z\le 54$. The reduced coupling matrix elements have been combined with an absorbing-sphere model based on the Landau-Zener method to obtain a relatively simple formalism for obtaining the electron transfer total cross sections. The method assumes a large number of final product channels available for reaction and is applicable for relative velocities $v_{\mathrm{rel}}\le 1\times {10}^8$ cm/sec. For such electron transfer reactions, the cross sections at a given velocity are dependent primarily on the charge state of the incident ion and the ionization potential of the target atom; also, for a given colliding pair, the cross section is found to be almost independent of the relative velocity. Cross sections have been calculated for H, He, Ne, Ar, Kr, Xe, and ${\mathrm{H}}_2$ targets. For the cases of ${\mathrm{H}}_2$ and Ar there are experimental data available; the comparison between theory and experiment is quite favorable.