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Demixing behavior in two-dimensional mixtures of anisotropic hard bodies

Yuri Martinez-Raton·Enrique Velasco·Luis Mederos
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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.

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Yuri Martinez-Raton, Enrique Velasco, Luis Mederos. 2005-09-08. Demixing behavior in two-dimensional mixtures of anisotropic hard bodies. https://doi.org/10.1103/physreve.72.031703

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