Freezing of Colloidal Simple Fluids

Abstract

It is well-known that the Lennard-Jones potential provides a fair description of the phase diagram of a simple atomic fluid with a fluid-fluid critical point and a fluid-fluid-solid triple point. In this chapter we analyze the modifications occurring in the phase diagram of a simple fluid when the range of the attractions is reduced. We consider two different theoretical approaches based on the Gibbs-Bogoliubov inequality in order to evaluate the fluid and solid free energies. It is shown that for intermediate attractions the liquid phase disappears and the phase diagram only exhibits a fluid-solid transition. A further reduction of the range of the attractions leads to a phase diagram with a solid-solid critical point and a fluidsolid-solid triple point. These phase diagrams could be of relevance to the phase behavior of colloidal simple fluids.