Extending the Maier-Saupe theory to cybotactic nematics

Abstract

A theory of thermotropic nematic liquid crystals in which molecules form internally ordered clusters is presented. The formulation is based on the same mean field approximation and form of the anisotropic potential used in the Maier-Saupe theory. A uniaxial nematic and two macroscopically isotropic phases are predicted. One of the isotropic phases consists of thermodynamically stable clusters with internal orientational order. The nematic phase shows cybotactic order throughout its range of stability. This order persists above the transition temperature, either as a stable feature or as a pretransitional effect. The values of the order parameter and of the entropy change at the nematic to isotropic phase transition depend on the size of the clusters. The Maier-Saupe theory is obtained in the limit of extremely large or extremely small clusters.

19 pages, 4 figures

References in corpus (3)

• Thermotropic Biaxial Nematics: Spontaneous or Field-Stabilized?
• Biaxial nematics: symmetries, order domains and field-induced phase transitions
• Symmetries and alignment of biaxial nematic liquid crystals

Cited by in corpus (6)

• A Molecular Theory of the Nematic-Nematic Phase Transitions in Mesogenic Dimers
• Molecular simulation of hierarchical structures in bent-core nematics
• Atomistic simulations of nematic phases formed by cyano-biphenyl dimers
• Probing Molecular Ordering in the Nematic Phases of para-Linked Bimesogen Dimers through NMR Studies of Flexible Prochiral Solutes
• Polar molecular ordering in the Nx phase of bimesogens and enantiotopic discrimination in the NMR spectra of rigid prochiral solutes
• Theoretical Remarks on Cybotactic Clusters of Bent-Core Nematic Liquid Crystals in 1D Settings