Density Functional Theory for Chiral Nematic Liquid Crystals

S. Belli; S. Dussi; M. Dijkstra; R. van Roij

doi:10.1103/physreve.90.020503

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arXiv · 1404.2113

Density Functional Theory for Chiral Nematic Liquid Crystals

S. Belli·S. Dussi·M. Dijkstra·R. van Roij

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Abstract

Even though chiral nematic phases were the first liquid crystals experimentally observed more than a century ago, the origin of the thermodynamic stability of cholesteric states is still unclear. In this Letter we address the problem by means of a novel density functional theory for the equilibrium pitch of chiral particles. When applied to right-handed hard helices, our theory predicts an entropy-driven cholesteric phase, which can be either right- or left-handed, depending not only on the particle shape but also on the thermodynamic state. We explain the origin of the chiral ordering as an interplay between local nematic alignment and excluded-volume differences between left- and right-handed particle pairs.

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S. Belli, S. Dussi, M. Dijkstra, R. van Roij. 2014-04-08. Density Functional Theory for Chiral Nematic Liquid Crystals. https://doi.org/10.1103/physreve.90.020503

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