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arXiv · 0709.0249

First-order phase transitions in two-dimensional off-lattice liquid crystals

H. H. Wensink·R. L. C. Vink
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Abstract

We consider an off-lattice liquid crystal pair potential in strictly two dimensions. The potential is purely repulsive and short-ranged. Nevertheless, by means of a single parameter in the potential, the system is shown to undergo a first-order phase transition. The transition is studied using mean-field density functional theory, and shown to be of the isotropic-to-nematic kind. In addition, the theory predicts a large density gap between the two coexisting phases. The first-order nature of the transition is confirmed using computer simulation and finite-size scaling. Also presented is an analysis of the interface between the coexisting domains, including estimates of the line tension, as well as an investigation of anchoring effects.

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H. H. Wensink, R. L. C. Vink. 2007-09-03. First-order phase transitions in two-dimensional off-lattice liquid crystals. https://doi.org/10.1088/0953-8984%2F19%2F46%2F466109

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