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Updated: Jun 25, 2026

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
Abstract:
Molecular rotation has attracted much attention with respect to the development of artificial molecular motors, in an attempt to mimic the intelligent and useful functions of biological molecular motors. Random motion of molecular rotators--for example the 180 degree flip-flop motion of a rotatory unit--causes a rotation of the local structure. Here, we show that such motion is controllable using an external electric field and demonstrate how such molecular rotators can be used as polarization rotation units in ferroelectric molecules. In particular, m-fluoroanilinium forms a hydrogen-bonding assembly with dibenzo[18]crown-6, which was introduced as the counter cation of [Ni(dmit)(2)](-) anions (dmit(2-) = 2-thioxo-1,3-dithiole-4,5-dithiolate). The supramolecular rotator of m-fluoroanilinium exhibited dipole rotation by the application of an electric field, and the crystal showed a ferroelectric transition at 348 K. These findings will open up new strategies for ferroelectric molecules where a chemically designed dipole unit enables control of the nature of the ferroelectric transition temperature.
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