Critical phenomena and tricritical points in multicomponent systems

Abstract

If one adopts an appropriate point of view, the thermodynamic properties of fluid mixtures near critical points are analogous to those of a pure fluid. This point of view is developed for binary mixtures, of which the liquid-vapor critical line in 3He 4He is a particular example. Tricritical points arise in mixtures of three or more components. They are not analogous to critical points in pure fluids, but resemble tricritical points in superfluid 3He 4He mixtures and metamagnets.