Number of atoms interacting with a quasi-free electron in nonpolar liquids

An earlier theory of thermal electron transport in liquid rare gases and saturated hydrocarbons yielded the radius of density fluctuations, A, as fitting parameters. Here, these data are rationalized in terms of a simple scattering model and thermodynamic density fluctuation. Assuming that the electron interacts with the same number of atoms, N, in each liquid, the variation of A from liquid to liquid can be interpreted. Parameter estimation yields N ≊ 1800 meaning that a thermal quasi-free electron interacts simultaneuosly with some 1800 rare gas atoms or 60-120 hydrocarbon molecules.