Thermodynamics and phase behavior of the lamellar Zwanzig model

L. Harnau; D. G. Rowan; J. -P. Hansen

doi:10.1063/1.1521936

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arXiv · cond-mat/0207059

Thermodynamics and phase behavior of the lamellar Zwanzig model

L. Harnau·D. G. Rowan·J. -P. Hansen

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Abstract

Binary mixtures of lamellar colloids represented by hard platelets are studied within a generalization of the Zwanzig model for rods, whereby the square cuboids can take only three orientations along the $x$, $y$ or $z$ axes. The free energy is calculated within Rosenfeld's ''Fundamental Measure Theory'' (FMT) adapted to the present model. In the one-component limit, the model exhibits the expected isotropic to nematic phase transition, which narrows as the aspect ratio $ζ=L/D$ ($D$ is the width and $L$ the thickness of the platelets) increases. In the binary case the competition between nematic ordering and depletion-induced segregation leads to rich phase behaviour.

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L. Harnau, D. G. Rowan, J. -P. Hansen. 2002-07-02. Thermodynamics and phase behavior of the lamellar Zwanzig model. https://doi.org/10.1063/1.1521936

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