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arXiv · 0911.1991

Statistical Mechanics of Splay Flexoelectricity in Nematic Liquid Crystals

Subas Dhakal·Jonathan V. Selinger
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Abstract

We develop a lattice model for the splay flexoelectric effect in nematic liquid crystals. In this model, each lattice site has a spin representing the local molecular orientation, and the interaction between neighboring spins represents pear-shaped molecules with shape polarity. We perform Monte Carlo simulations and mean-field calculations to find the behavior as a function of interaction parameters, temperature, and applied electric field. The resulting phase diagram has three phases: isotropic, nematic, and polar. In the nematic phase, there is a large splay flexoelectric effect, which diverges as the system approaches the transition to the polar phase. These results show that flexoelectricity is a statistical phenomenon associated with the onset of polar order.

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Subas Dhakal, Jonathan V. Selinger. 2009-11-10. Statistical Mechanics of Splay Flexoelectricity in Nematic Liquid Crystals. https://doi.org/10.1103/physreve.81.031704

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