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Free planar isotropic-nematic interfaces in binary hard-rod fluids

Kostya Shundyak·Rene van Roij
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Abstract

Within the Onsager theory we study free planar isotropic-nematic interfaces in binary mixtures of hard rods. For sufficiently different particle shapes the bulk phase diagrams of these mixtures exhibit a triple point, where an isotropic (I) phase coexists with two nematic phases ($N_1$ and $N_2$) of different composition. For all explored mixtures we find that upon approach of the triple point the $IN_2$ interface shows complete wetting by an intervening $N_1$ film. We compute the surface tensions of isotropic-nematic interfaces, and find a remarkable increase with fractionation, similar to the effect in polydisperse hard-rod fluids.

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Kostya Shundyak, Rene van Roij. 2003-09-17. Free planar isotropic-nematic interfaces in binary hard-rod fluids. https://doi.org/10.1103/physreve.68.061703

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