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Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Nonisothermal model for the direct isotropic/smectic-A liquid-crystalline transition
Nasser Mohieddin Abukhdeir1, Alejandro D Rey
1Department of Chemical Engineering, McGill University, Montréal, Québec, Canada.
Langmuir : the ACS Journal of Surfaces and Colloids
|October 1, 2009
Summary
This study extends a liquid crystal phase transition model to include thermal effects. Simulations show nonisothermal conditions alter growth predictions and reveal novel phase-transformation kinetics.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Physical Chemistry
Background:
- The isotropic/smectic-A liquid-crystalline phase transition is crucial for display technologies.
- Existing models often simplify thermal effects, limiting accuracy under nonisothermal conditions.
Purpose of the Study:
- To extend a high-order model for the isotropic/smectic-A transition by incorporating thermal effects.
- To investigate the impact of anisotropic thermal diffusion and latent heat on phase transition dynamics.
- To compare nonisothermal simulations with isothermal ones and analyze deviations from standard predictions.
Main Methods:
- Development of an extended high-order model accounting for anisotropic thermal diffusion and latent heat.
- Implementation of multiscale multitransport simulations for the nonisothermal model.
- Comparison of nonisothermal simulation results with isothermal simulations and the Landau-de Gennes theory.
Main Results:
- The extended model accurately predicts diffusion-limited growth under shallow quench conditions, correcting standard Landau-de Gennes predictions.
- Nonisothermal simulations reveal metastable nematic preordering preceding smectic-A growth.
- Novel nonmonotonic phase-transformation kinetics were observed during nonisothermal simulations.
Conclusions:
- Thermal effects significantly influence liquid crystal phase transition dynamics, particularly under nonisothermal conditions.
- The developed model provides a more accurate description of phase transitions compared to isothermal models.
- The observed nonmonotonic kinetics offer new insights into the complex behavior of liquid crystal phase ordering.
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