Self-Trapping of Electrons in Fluid Neon

A light particle can self-trap in a classical fluid by self-consistently modifying the fluid density around itself. The fundamental equation of thermodynamics in the entropy formulation for such a system is presented. The equation includes terms that describe the possible nucleation of a heterophase region by the self-trapping, either a liquid drop within a vapor or a vapor bubble in a liquid, and the resulting interfacial terms which contribute. A pseudo-potential is used to describe the interaction of the light particle with the fluid atoms. The variational principle is applied to extremize the entropy and a coupled set of self-consistent equations results. The equations are then solved numerically for the case of excess electrons in fluid neon. The van der Waals approximation for fluid neon is used. The size and stability of electron self -trapped states are calculated as functions of the fluid density and temperature. The thermally averaged mobility of an ensemble of trapped and quasi-free electrons in the fluid is derived. Theoretical calculations are then compared with recent experimental measurements of the mobility of excess electrons in fluid and liquid neon.