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Updated: Jun 25, 2026
07:03
Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
Ferroelectricity and polarity control in solid-state flip-flop supramolecular rotators
Tomoyuki Akutagawa1, Hiroyuki Koshinaka, Daisuke Sato
1Research Institute for Electronic Science, Hokkaido University, Sapporo 001-0020, Japan. takuta@es.hokudai.ac.jp
Nature Materials
|February 10, 2009
Summary
Researchers demonstrate controllable molecular rotation using electric fields. This breakthrough enables molecular rotators to function as polarization units in ferroelectric materials, paving the way for novel ferroelectric molecule design.
Area of Science:
- Supramolecular Chemistry
- Materials Science
- Molecular Engineering
Background:
- Artificial molecular motors are inspired by biological systems.
- Molecular rotators exhibit random motion, influencing local structures.
- Controlling molecular rotation is key for advanced molecular devices.
Purpose of the Study:
- To demonstrate electric field control over molecular rotator motion.
- To utilize molecular rotators as polarization rotation units in ferroelectric molecules.
- To explore new strategies for designing ferroelectric materials.
Main Methods:
- Formation of hydrogen-bonding assemblies between m-fluoroanilinium and dibenzo[18]crown-6.
- Introduction of [Ni(dmit)(2)](-) anions as counterions.
- Application of external electric fields to induce dipole rotation.
Main Results:
- The supramolecular rotator of m-fluoroanilinium showed controllable dipole rotation under an electric field.
- The crystal exhibited a ferroelectric transition at 348 K.
- Chemically designed dipole units were shown to influence ferroelectric transition temperatures.
Conclusions:
- Electric field control of molecular rotation is achievable.
- Molecular rotators can serve as polarization units in ferroelectric molecules.
- This work offers new strategies for tailoring ferroelectric properties through molecular design.
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