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arXiv · 1603.05158

A Landau-de Gennes theory for hard colloidal rods: defects and tactoids

Jeffrey Everts·Melle Punter·Sela Samin·Paul van der Schoot·René van Roij
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Abstract

We construct a phenomenological Landau-de Gennes theory for hard colloidal rods by performing an order parameter expansion of the chemical-potential dependent grand potential. By fitting the coefficients to known results of Onsager theory, we are not only able to describe the isotropic-nematic phase transition as function of density, including the well-known density jump, but also the isotropic-nematic planar interface. The resulting theory is applied in calculations of the isotropic core size in a radial hedgehog defect, the density dependence of linear defects of hard rods in square confinement, and the formation of a nematic droplet in an isotropic background.

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Jeffrey Everts, Melle Punter, Sela Samin, Paul van der Schoot, René van Roij. 2016-05-18. A Landau-de Gennes theory for hard colloidal rods: defects and tactoids. https://doi.org/10.1063/1.4948785

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