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Updated: Aug 2, 2025
07:03
Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
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Determination of tilt angle and its behavior in chiral smectic phases by exploring molecular conformations using
A Deptuch1, T Jaworska-Gołąb2, M Dziurka3
1Institute of Nuclear Physics Polish Academy of Sciences, Radzikowskiego 152, PL-31342 Kraków, Poland.
Physical Review. E
|April 19, 2023
Summary
Computational modeling reveals that C-shaped molecular structures accurately predict the tilt angle in ferroelectric and antiferroelectric liquid crystal phases. This finding is crucial for understanding liquid crystal behavior.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Computational Chemistry
Background:
- Ferroelectric and antiferroelectric liquid crystals exhibit complex phase behaviors.
- Understanding molecular structure-property relationships is key to designing advanced materials.
Purpose of the Study:
- To computationally evaluate the tilt angle in ferroelectric smectic C* and antiferroelectric smectic C(A)* phases.
- To investigate the influence of molecular conformation and shape on liquid crystal properties.
Main Methods:
- Density functional theory (DFT) calculations.
- X-ray diffraction techniques.
- Computational modeling of molecular conformations (fully extended, gauche) and shapes (hockey stick, zigzag, C shape).
Main Results:
- C-shaped molecular structures, in both extended and gauche conformations, accurately predict tilt angles.
- Agreement was found between computational and electro-optical measurement data below saturation temperature.
- The study confirmed the presence of standard orthogonal SmA* and de Vries SmA* phases in specific homologues.
Conclusions:
- The C-shaped molecular structure is adopted by molecules in the studied smectogen series.
- Computational methods, particularly those considering molecular shape, are effective for predicting liquid crystal phase behavior.
- This research provides insights into the structural basis of ferroelectricity and antiferroelectricity in liquid crystals.
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