Approaches to the Tricritical Point in Quasibinary Fluid Mixtures

Abstract

When the Griffiths theory of tricritical points is extended to the eighth power of the order parameter, certain composition differences preserve the limiting behavior far from the tricritical point, an unexpected result that had been overlooked in earlier van der Waals model calculations. New calculations show that, along a path of constant tricritical composition and density and increasing temperature, a quasibinary system goes from two phases to one at the tricritical point, with no appearance of the third phase.