Theory of excess-electron mobility in compressed argon

Abstract

The purpose of this paper is to calculate the mobility of excess electrons in compressed argon (20-100 atm) both in single-scattering and multiple-scattering approximations. Calculations in the single-scattering approximation are carried out with the aid of the Cohen-Lekner theory. A new formula for the mobility of excess electrons in the multiple-scattering approximation is derived from the Kubo-Greenwood relation for electric conductivity. Numerical results inferred from this formula and from the Cohen-Lekner theory are compared with the experimental data reported in the literature. The results obtained in this paper indicate that the Cohen-Lekner theory is applicable only at very low densities of gaseous argon and that inclusion of the long-range part of the electron-atom potential gives a significant improvement in the theoretical results. The multiple-scattering corrections have been estimated to be about (10-25)% of the value of mobility calculated in the single-scattering approximation.