Exact equations of state for nematics

Journal Article · Sat Sep 15 04:00:00 EDT 2018 · Annals of Physics

DOI:https://doi.org/10.1016/J.AOP.2018.07.016· OSTI ID:22848382

Giglio, Francesco; Moro, Antonio ^[1]

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1. Department of Mathematics, Physics and Electrical Engineering, University of Northumbria at Newcastle (United Kingdom)

We propose a novel approach to the solution of nematic Liquid Crystal models based on the derivation of a system of nonlinear wave equations for order parameters such that the occurrence of uniaxial and biaxial phase transitions can be interpreted as the propagation of a two-dimensional shock wave in the space of thermodynamic parameters. We obtain the exact equations of state for an integrable model of biaxial nematic liquid crystals and show that the classical transition from isotropic to uniaxial phase in absence of external fields is the result of a van der Waals type phase transition, where the jump in the order parameters is a classical shock generated from a gradient catastrophe at a non-zero isotropic field. The study of the equations of state provides the first analytical description of the rich structure of nematics phase diagrams in presence of external fields.

• OSTI ID: 22848382
• Journal Information: Annals of Physics, Journal Name: Annals of Physics Vol. 396; ISSN APNYA6; ISSN 0003-4916
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CRYSTAL MODELS
EQUATIONS OF STATE
LIQUID CRYSTALS
ORDER PARAMETERS
PHASE DIAGRAMS
PHASE TRANSFORMATIONS
SHOCK WAVES
THERMODYNAMICS
TWO-DIMENSIONAL CALCULATIONS
VAN DER WAALS FORCES
WAVE EQUATIONS