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Updated: Aug 11, 2026
06:26
Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Density functional theory of liquid crystals and surface anchoring
M Moradi1, Richard J Wheatley, A Avazpour
1Department of Physics, College of Science, Shiraz University, Shiraz 71454, Iran. moradi@physics.susc.ac.ir
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|February 21, 2006
Summary
Density functional theory models confined liquid crystals with ellipsoidal particles. The study reveals homeotropic anchoring for short needles and planar anchoring for long needles, validating density and order parameter profiles near walls.
Area of Science:
- Physics
- Materials Science
- Computational Chemistry
Background:
- Liquid crystals exhibit unique properties due to molecular ordering.
- Confining liquid crystals alters their bulk behavior and surface interactions.
- Understanding particle interactions and surface anchoring is crucial for device applications.
Purpose of the Study:
- To apply density functional theory (DFT) to confined liquid crystals with ellipsoidal particles.
- To extend the restricted orientation model for studying surface anchoring effects.
- To investigate density and orientational order parameter profiles under confinement.
Main Methods:
- Utilized density functional theory with the hard Gaussian overlap (HGO) potential.
- Extended Rickayzen's restricted orientation model to include surface anchoring.
- Approximated the pair direct correlation function (DCF) using Percus-Yevick theory for hard spheres.
- Employed a hard needle-wall potential to model particle-wall interactions.
Main Results:
- Observed homeotropic anchoring for short needle lengths and planar anchoring for long needle lengths.
- Calculated density and order parameter profiles for confined HGO fluids.
- Achieved agreement with Monte Carlo simulations for bulk isotropic phase density and order parameters.
- Found satisfactory agreement for density profiles and near-wall order parameters in the nematic phase.
Conclusions:
- DFT effectively models confined liquid crystals with HGO interactions.
- Particle shape and wall interactions dictate surface anchoring behavior (homeotropic vs. planar).
- The model shows good agreement with simulations, particularly near confining walls, but requires refinement for bulk regions.
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