Phase diagram of mixtures of hard colloidal spheres and discs: a free-volume scaled-particle approach.

Van't Hoff Laboratory for Physical and Colloid Chemistry, Debye Institute, Utrecht University, Padualaan 8, 3584CH Utrecht, The Netherlands.
The Journal of Chemical Physics (Impact Factor: 3.12). 03/2004; 120(5):2470-4. DOI: 10.1063/1.1637573
Source: PubMed

ABSTRACT Phase diagrams of mixtures of colloidal hard spheres with hard discs are calculated by means of the free-volume theory. The free-volume fraction available to the discs is determined from scaled-particle theory. The calculations show that depletion induced phase separation should occur at low disc concentrations in systems now experimentally available. The gas-liquid equilibrium of the spheres becomes stable at comparable size ratios as with bimodal mixtures of spheres or mixtures of rods and spheres. Introducing finite thickness of the platelets gives rise to a significant lowering of the fluid branch of the binodal.

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