Phase behavior of weakly polydisperse sticky hard spheres: Perturbation theory for the Percus-Yevick solution

Abstract

We study the effects of size polydispersity on the gas-liquid phase behaviour of mixtures of sticky hard spheres. To achieve this, the system of coupled quadratic equations for the contact values of the partial cavity functions of the Percus-Yevick solution is solved within a perturbation expansion in the polydispersity, i.e. the normalized width of the size distribution. This allows us to make predictions for various thermodynamic quantities which can be tested against numerical simulations and experiments. In particular, we determine the leading-order effects of size polydispersity on the cloud curve delimiting the region of two-phase coexistence and on the associated shadow curve; we also study the extent of size fractionation between the coexisting phases. Different choices for the size-dependence of the adhesion strengths are examined carefully; the Asakura-Oosawa model of a mixture of polydisperse colloids and small polymers is studied as a specific example.

43 pages, 12 figures, and 1 table

References in corpus (4)

• Fractionation effects in phase equilibria of polydisperse hard sphere colloids
• Stability boundaries, percolation threshold, and two phase coexistence for polydisperse fluids of adhesive colloidal particles
• The thermodynamic instabilities of a binary mixture of sticky hard spheres
• On the equivalence between the energy and virial routes to the equation of state of hard-sphere fluids

Cited by in corpus (7)

• Patchy sticky hard spheres: analytical study and Monte Carlo simulations
• Multicomponent adhesive hard sphere models and short-ranged attractive interactions in colloidal or micellar solutions
• Phase behavior of polydisperse sticky hard spheres: analytical solutions and perturbation theory
• Measuring local volume fraction, long-wavelength correlations and fractionation in a phase-separating polydisperse fluid
• Weakly polydisperse systems: Perturbative phase diagrams that include the critical region
• The moment sum-rules for ionic liquids at criticality
• Monte Carlo simulation of Hard-, Square-Well, and Square-Shoulder Disks in narrow channels