Phase transitions in three-component fluid systems

Abstract

We prove the existence of phase segregation in a three component Widom-Rowlinson fluid mixture with activities εA=εB=ε≥εc. for sufficiently large ε. Integration over the coordinates of one component in a three-component Widom-Rowlinson Model yields a binary systems with hard core plus attractive many body potentials. We investigate some features of the phase diagram of such a binary mixture using the results of mean field theory and of series expansion for the three-component Widom-Rowlinson model. We also find a general way of obtaining the equation of state of multi-component one-dimensinal systems with non-additive hard core diameters and nearest neighbor soft potentials.