Realization of Electrical Response by Controlling the "Direction" and "Shape" of Spinning Molecules - Expectations for Application to Devices Capable of Storing Information at Higher Densities than Previously Possible

【Key points of the study】

• We discovered that "Plastic crystal (*1)", which have properties between those of solids and liquids, respond electrically in two stages due to changes in molecular orientation and shape.

• This is the first example of a cooperative, two-step electrical response found in Plastic crystal, where molecules have been thought to rotate randomly, and is considered a new type of functional material different from conventional ferroelectrics (*2).

• This phenomenon is expected to contribute to next-generation technology called "Multilevel memory", which can store not only the conventional "0" and "1" but also multiple pieces of information (e.g., "0," "1," "2," and "3"), and to the development of new types of sensors and switches.

【Summary】
Improving the performance of smartphones and computers that support our daily lives requires new material technologies that can store more information in the same size.

A collaborative research group including Professor Motohiro Mizuno, Nanomaterials Research Institute, Kanazawa University, Assistant Professor Takuya Kurihara, Faculty of Chemistry, Institute of Science and Engineering, Kanazawa University, Graduate Student Nozomi Onodera (Graduate School of Engineering),  Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Assistant Professor Shun Dekura and Professor Tomoyuki Akutagawa, Tohoku University, has for the first time captured a unique electrical response phenomenon in "plastic crystals," a material in which the orientation and shape of the molecules change when electricity is applied, and the state can be maintained.

This is like electrically operating two switches, "orientation" and "shape" of molecules, and paves the way for the realization of "multilevel memory," which can handle more information than conventional memory devices. This achievement is expected to serve as a basis for contributing to the further development of the information society.

The results of this research were published on May 25, 2025 (U.S. local time) in the scientific journal "Journal of the American Chemical Society"? The article was published online.

Image of a Plastic Crystal  : Sucinonitrile changing its shape from trans conformation to gauche conformation

【Glossary】
*1  Plastic crystal
One of the solid-liquid intermediate phases in which the constituent molecules can rotate and move relatively freely in a crystal lattice, even though it is a solid. It is named after its wax-like softness (plasticity). In contrast, liquid crystals are an intermediate phase that has the fluidity of a liquid but the orientation of its molecules is aligned like that of a solid, and is a counterpart to Plastic crystal.

*2  Ferroelectric
A material that is spontaneously polarized even in the absence of an external electric field and whose polarization direction can be reversed by an external electric field. Used in nonvolatile memory, etc.

Click here to see the press release【Japanese only】

Journal : Journal of the American Chemical Society

Researcher Information : Motohiro Mizuno
　　　　　　Takuya Kurihara

Related Information

School of Chemistry, College of Science and Engineering, Kanazawa University : https://chemistry.w3.kanazawa-u.ac.jp/

Graduate School of Natural Science and Technology, Kanazawa University : https://www.nst.kanazawa-u.ac.jp/