Computational molecular field theory for nematic liquid crystals

Abstract

Nematic liquid crystals exhibit configurations in which the underlying ordering changes markedly on macroscopic length scales. Such structures include topological defects in the nematic phase and tactoids within nematic-isotropic coexistence. We discuss a computational study of inhomogeneous configurations that is based on a field theory extension of the Maier-Saupe molecular model of a uniaxial, nematic liquid crystal. A tensor order parameter is defined as the second moment of an orientational probability distribution, leading to a free energy that is not convex within the isotropic-nematic coexistence region, and that goes to infinity if the eigenvalues of the order parameter become non-physical. Computations of the spatial profile of the order parameter are presented for an isotropic-nematic interface in one dimension, a tactoid in two dimensions, and a nematic disclination in two dimensions. We compare our results to those given by the Landau de-Gennes free energy for the same configurations and discuss the advantages of such a model over the latter.

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Cited by in corpus (6)

• Singularity identification for the characterization of topology, geometry, and motion of nematic disclination lines
• Numerical method for the equilibrium configurations of a Maier-Saupe bulk potential in a Q-tensor model of an anisotropic nematic liquid crystal
• Kinematics and dynamics of disclination lines in three-dimensional nematics
• Anisotropic disclination cores in nematic liquid crystals modelled by a self consistent molecular field theory
• Equilibrium morphology of tactoids in elastically anisotropic nematics
• A computational study of nematic core structure and disclination interactions in elastically anisotropic nematics