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Updated: Oct 23, 2025
06:26
Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
7.3K
Conically degenerate anchoring effect in planar nematic-liquid-crystal shells.
Seyed Reza Seyednejad1, Mohammad Reza Mozaffari2
1Institute for Advanced Studies in Basic Sciences, Zanjan 45195-159, Iran.
Physical Review. E
|August 20, 2021
Summary
We investigated defect textures in nematic-liquid-crystal shells, finding stable configurations independent of shell thickness. In thin shells, boojums transform into two disclination curves, revealing key structural changes.
Area of Science:
- Soft Matter Physics
- Liquid Crystal Science
- Materials Science
Background:
- Nematic-liquid-crystal shells exhibit complex defect textures.
- Surface anchoring conditions significantly influence molecular orientation.
- Understanding these textures is crucial for applications in optics and displays.
Purpose of the Study:
- To analyze defect textures in symmetric and asymmetric nematic-liquid-crystal shells.
- To investigate the impact of conic and planar surface anchorings.
- To determine equilibrium nematic orientations and their stability.
Main Methods:
- Numerical minimization of Landau-de Gennes free energy.
- Implementation of surface potentials on spherical shell boundaries.
- Analysis of director field configurations in thick and thin shells.
Main Results:
- Symmetric nematic shells achieve stable configurations irrespective of shell thickness.
- Thick shells display bipolar and hexadecapolar director field patterns.
- Thin shells show boojums transforming into two stable disclination curves.
Conclusions:
- Shell thickness does not affect the energetic stability of symmetric nematic configurations.
- The transition from bulk-like to confined behavior in thin shells leads to significant changes in defect topology.
- This study provides insights into the fundamental behavior of confined liquid crystals.
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