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Paradoxes for chromonic liquid crystal droplets
Silvia Paparini1, Epifanio G Virga1
1Dipartimento di Matematica, Università di Pavia, Via Ferrata 5, 27100 Pavia, Italy.
Physical Review. E
|November 18, 2022
Summary
Novel lyotropic phases, chromonic liquid crystals, exhibit unique elastic properties. Violating classical liquid crystal theory, their tactoids disintegrate into smaller droplets, revealing paradoxical behaviors.
Area of Science:
- Materials Science
- Soft Matter Physics
- Liquid Crystals
Background:
- Chromonic liquid crystals represent a novel lyotropic phase.
- Existing models use Oseen-Frank theory, assuming twist constant << saddle-splay constant.
- This assumption violates Ericksen inequalities.
Purpose of the Study:
- Investigate the consequences of violating Ericksen inequalities in chromonic liquid crystals.
- Analyze the behavior of chromonic liquid crystal droplets in isotropic fluids.
- Explore the implications for tactoid stability and structure.
Main Methods:
- Theoretical modeling of elastic properties.
- Analysis of liquid crystal droplet behavior.
- Application of modified Oseen-Frank theory.
Main Results:
- Demonstrated paradoxical consequences arising from the violation of Ericksen inequalities.
- Observed indefinite disintegration of tactoids with degenerate planar anchoring.
- Identified spontaneous fragmentation into numerous smaller droplets.
Conclusions:
- The classical Oseen-Frank theory, under specific conditions, leads to non-physical predictions for chromonic liquid crystals.
- The violation of Ericksen inequalities is crucial for understanding the unique behavior of these materials.
- Droplet disintegration highlights novel instability mechanisms in lyotropic systems.
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