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Updated: Jul 18, 2026
07:03
Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
Chirality and polarity transfers between bent-core smectic liquid-crystal substances
A Jákli1, G Liao, I Shashikala
1Chemical Physics Interdisciplinary Program and Liquid Crystal Institute, Kent State University, Kent, Ohio 44242, USA.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|December 13, 2006
Summary
Chiral liquid crystals exhibit unique properties. This study shows molecular chirality influences polarization in banana phases only in synclinic configurations, offering insights into advanced material design.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Liquid Crystal Science
Background:
- Liquid crystals possess unique solid-like and liquid-like characteristics.
- Chirality can manifest at both molecular and mesoscopic levels in liquid crystals.
- Bent-core mesogens are of interest due to their unique phase behaviors.
Purpose of the Study:
- To investigate the interplay of molecular chirality and mesophase polarization in binary liquid crystal mixtures.
- To understand the contribution of molecular chirality to the polarization of bent-core smectic phases.
- To explore the influence of mixing a chiral dimer with an achiral bent-core mesogen on liquid crystal properties.
Main Methods:
- Synthesis and characterization of a chiral dimer (B-Ch) and an achiral bent-core mesogen (B-2F).
- Formation of binary composites by mixing B-Ch and B-2F.
- Measurement of polarization (P(c) and P(b)) in pure and mixed liquid crystal phases.
- Analysis of phase symmetries (C2, SmC*, SmCP) and configurations (synclinic, anticlinic).
Main Results:
- Pure B-Ch exhibits a chiral smectic C (SmC*) phase with P(c) ~ 30 nC/cm².
- Pure B-2F shows a synclinic and anticlinic antiferroelectric banana smectic (SmCP) phase with P(b) ~ 900 nC/cm².
- In binary mixtures, molecular chirality (from B-Ch) was found to contribute to the polarization of banana phases exclusively in synclinic configurations.
Conclusions:
- The study elucidates the specific conditions under which molecular chirality impacts the macroscopic polarization of bent-core liquid crystal phases.
- The findings highlight the importance of phase configuration (synclinic vs. anticlinic) in determining the role of chirality in polarization.
- This research provides fundamental insights for designing liquid crystal materials with tailored electro-optical properties.
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