Demixing behavior in two-dimensional mixtures of anisotropic hard bodies

Abstract

Scaled particle theory for a binary mixture of hard discorectangles and for a binary mixture of hard rectangles is used to predict possible liquid-crystal demixing scenarios in two dimensions. Through a bifurcation analysis from the isotropic phase, it is shown that isotropic-nematic demixing is possible in two-dimensional liquid-crystal mixtures composed of hard convex bodies. This bifurcation analysis is tested against exact calculations of the phase diagrams in the framework of the restricted-orientation two-dimensional model (Zwanzig model). Phase diagrams of a binary mixture of hard discorectangles are calculated through the parametrization of the orientational distribution functions. The results show not only isotropic-nematic, but also nematic-nematic demixing ending in a critical point, as well as an isotropic-nematic-nematic triple point for a mixture of hard disks and hard discorectangles.

arXiv comment13 pages, 14 figures. To appear in PRE

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Cited by in corpus (15)

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• Demixing and tetratic ordering in some binary mixtures of hard superellipses
• Phase diagram of a bidispersed hard rod lattice gas in two dimensions
• Role of length-polydispersity on the phase behavior of freely-rotating hard-rectangle fluid
• Three stable phases and thermodynamic anomaly in a binary mixture of hard particles
• Effect of clustering on the orientational properties of a fluid of hard right isosceles triangles
• Thermodynamic behavior of binary mixtures of hard spheres: Semianalytical solutions on a Husimi lattice built with cubes
• Fluid-fluid versus fluid-solid demixing in mixtures of parallel hard hypercubes
• Fluid-fluid demixing and density anomaly in a ternary mixture of hard spheres
• Exotic liquid crystalline phases in monolayers of vertically vibrated granular particles
• Density-functional theory for clustering of two-dimensional hard particle fluids