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Updated: Jul 23, 2025
08:37
Forming, Confining, and Observing Microtubule-Based Active Nematics
Published on: January 13, 2023
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Thin pyramidal cones in nematic liquid crystals.
Seyed Reza Seyednejad1, Saeedeh Shoarinejad2, Mohammad Reza Mozaffari3
1Institute for Advanced Studies in Basic Sciences, Zanjan 45195-159, Iran.
Physical Review. E
|July 19, 2023
Summary
Researchers studied hollow pyramidal cone shells in nematic liquid crystals. These particles form unique structures and interactions, influencing director distortions and defect patterns.
Area of Science:
- Soft Matter Physics
- Materials Science
- Colloid Science
Background:
- Nematic liquid crystals exhibit unique orientational order.
- Colloidal particles can influence and interact with nematic order.
- Pyramidal cone shells present novel geometries for colloidal studies.
Purpose of the Study:
- Investigate the arrangement and interactions of hollow pyramidal cone shells in a nematic host.
- Analyze the influence of shell thickness on nematic coherence length.
- Determine the colloidal behavior using free energy minimization and surface energy.
Main Methods:
- Minimization of Landau-de Gennes free energy.
- Inclusion of Fournier surface energy.
- Application of the finite element method for numerical simulations.
- Analysis of particle orientation (parallel and perpendicular to the far director).
Main Results:
- Colloidal pyramidal cones exhibit both parallel and perpendicular orientations relative to the director.
- Parallel alignment leads to splay director distortion and boojum defects at shell tips.
- Perpendicular alignment results in bending distortion without defect patterns.
- These structures induce long-range dipolar interactions and can form nested configurations.
Conclusions:
- Hollow pyramidal cone shells serve as versatile building blocks in nematic systems.
- The orientation of these shells dictates distinct director distortions and defect formations.
- The induced dipolar interactions facilitate the self-assembly of complex colloidal structures.
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