Electronic and molecular transport in fluids

The motion of excess electrons in liquid argon is considered using the kinetic equation approach of Cohen and Lekner. Their solution of the Boltzmann Equation gives both a qualitative and quantitative description of the mobility of an excess electron in liquid argon at high densities, but fails to describe the zero field mobility maximum as a function of density. This is shown to be due to their incorrect handling of the long range electron-atom interaction potential. An interaction potential is proposed that contains the features expected of a reasonable electron-atom interaction and which also describes the mobility maximum as a function of density. The extension of Cohen and Lekner's theory to molecules having internal modes is presented. It is shown that the more rapidly the scattering length autocorrelation function decays the larger the fractional energy loss per collision, therefore explaining why the mobilities of electrons in most hydrocarbons are constant up to very high fields.