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Updated: Jul 4, 2026
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High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
Thermal diffusivity and the conformal transformation on nematic liquid crystals
M Simões1, A J Palangana, A Steudel
1Departamento de Física, Universidade Estadual de Londrina, Campus Universitário, 86051-990-Londrina (PR), Brazil. simoes@uel.br
Summary
This study investigates thermal diffusivity anisotropy in nematic liquid crystals using theory and experiments. The Baalss-Hess transformation provides a parameter-free model, confirming diffusivity is higher along the director for calamitic phases and perpendicular for discotic phases.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Physical Chemistry
Background:
- Nematic liquid crystals exhibit anisotropic thermal properties.
- Understanding thermal diffusivity is crucial for their applications.
Purpose of the Study:
- To theoretically and experimentally investigate the anisotropy of thermal diffusivity in nematic liquid crystals.
- To apply the Baalss-Hess conformal transformation for a parameter-free model.
- To compare theoretical predictions with experimental data across different nematic phases.
Main Methods:
- Theoretical analysis using the Baalss-Hess conformal transformation.
- Experimental measurements of thermal diffusivity.
- Comparison of theoretical results with experimental data for calamitic and discotic nematic phases.
Main Results:
- A parameter-free theoretical equation for heat diffusion anisotropy was derived.
- Experimental data partially confirmed that thermal diffusivity is greater along the director in calamitic nematic phases.
- Experimental data supported the prediction of higher diffusivity perpendicular to the director in discotic nematic phases.
Conclusions:
- The Baalss-Hess transformation is effective in modeling thermal diffusivity anisotropy in nematic liquid crystals.
- The study confirms distinct thermal diffusivity behaviors in calamitic versus discotic nematic phases.
- Experimental validation across lyotropic and thermotropic phases supports the theoretical framework.
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