Shape of the binodal curves at a critical endpoint.

Using a recently developed expansion technique, the binodal, or coexistence, curves at a critical endpoint have been determined within the Griffiths thermodynamic model of multicomponent fluids. The binodal curve of the spectator phase shows a "4/3" singularity, or more generally a (delta + 1)/delta singularity. The binodal of the critical phase, however, shows no evidence of this singularity.