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Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
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Topological phase transitions in two-dimensional bent-core liquid crystal models.
B Kamala Latha1, Surajit Dhara1, V S S Sastry2
1School of Physics, University of Hyderabad, Hyderabad 500046, India.
Physical Review. E
|January 15, 2022
Summary
Interacting V-shaped liquid crystal (LC) molecules undergo two temperature-driven transitions, forming uniaxial then biaxial phases. These transitions are driven by topological ordering of point disclinations.
Area of Science:
- Condensed matter physics
- Materials science
- Statistical mechanics
Background:
- Investigating liquid crystal (LC) models with V-shaped bent-core molecules.
- Exploring molecular interactions and reorientations in three dimensions on a square lattice.
Purpose of the Study:
- To investigate two-dimensional liquid crystal models of interacting V-shaped bent-core molecules.
- To understand temperature-driven topological transitions and resulting uniaxial and biaxial phases.
Main Methods:
- Utilizing Monte Carlo simulations to compute system energy, specific heat, and order parameters.
- Analyzing temperature dependencies of topological order parameters and defect densities.
- Examining correlation functions for molecular axis orientations.
Main Results:
- Observed two temperature-driven topological transitions mediated by point disclinations.
- Identified successive condensation into uniaxial and biaxial phases.
- Found exponential decay in disordered phase and power-law decay in biaxial phase for correlation functions.
Conclusions:
- The study reveals distinct temperature-driven transitions leading to uniaxial and biaxial symmetries in bent-core liquid crystals.
- Cross-coupling between uniaxial and biaxial tensors is significant, influenced by molecular geometry.
- The simplified model highlights the role of molecular shape (θ) in phase behavior.
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