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Published on: April 8, 2018
Induced antiferroelectric smectic- C(*)(A) phase by doping ferroelectric- C* phase with bent-shaped molecules
1Department of Organic and Polymeric Materials, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8552, Japan and Department of Chemistry, Warsaw University, Al.Zwirki I Wigury 101, 02-089 Warsaw, Poland.
Physical Review Letters
|September 8, 2000
Summary
Doping ferroelectric Sm-C(*) liquid crystals with bent-shaped molecules induces an antiferroelectric Sm-C(*)(A) phase. These molecules reorient under electric fields, influencing interlayer ordering.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Organic Chemistry
Background:
- Ferroelectric liquid crystals (Sm-C(*)) exhibit spontaneous polarization.
- Antiferroelectric ordering (Sm-C(*)(A)) is a distinct phase with unique electro-optic properties.
- Controlling interlayer interactions is key to manipulating liquid crystal phases.
Purpose of the Study:
- To investigate the effect of doping ferroelectric Sm-C(*) phases with bent-shaped molecules.
- To understand the mechanism of induced antiferroelectric Sm-C(*)(A) phase formation.
- To elucidate the molecular reorientation behavior under electric fields.
Main Methods:
- Electro-optic measurements to observe phase transitions.
- Dielectric spectroscopy to probe polarization dynamics.
- Fourier-transform infrared (FTIR) spectroscopy to analyze molecular structure and orientation.
Main Results:
- Doping with bent-shaped molecules successfully induced the antiferroelectric Sm-C(*)(A) phase.
- Systems with weak interlayer interactions showed controllable anticlinic-synclinic ordering.
- FTIR indicated that bent-shaped molecules are non-planar and reorient with carbonyl groups in the smectic plane upon electric field application.
Conclusions:
- Bent-shaped molecules can effectively dope ferroelectric Sm-C(*) phases to create antiferroelectric Sm-C(*)(A) phases.
- Molecular non-planarity and reorientation are crucial for inducing and controlling antiferroelectric ordering.
- External electric fields can manipulate the molecular arrangement and phase behavior in these liquid crystal systems.
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