A Ferroelectric Metallomesogen Exhibiting Field-Induced Slow Magnetic Relaxation

Ryohei Akiyoshi; Hikaru Zenno; Yoshihiro Sekine; Manabu Nakaya; Motoko Akita; Daisuke Kosumi; Leonard F Lindoy; Shinya Hayami

doi:10.1002/chem.202103367

A Ferroelectric Metallomesogen Exhibiting Field-Induced Slow Magnetic Relaxation

Chemistry. 2022 Jan 24;28(5):e202103367. doi: 10.1002/chem.202103367. Epub 2021 Dec 16.

Authors

Ryohei Akiyoshi¹, Hikaru Zenno¹, Yoshihiro Sekine^{1

2}, Manabu Nakaya³, Motoko Akita⁴, Daisuke Kosumi^{5

6}, Leonard F Lindoy⁷, Shinya Hayami^{1

6}

Affiliations

¹ Department of Chemistry, Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto, 860-8555, Japan.
² Priority Organization for Innovation and Excellence, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto, 860-8555, Japan.
³ Department of Chemistry, Faculty of Science, Josai University, 1-1 Keyakidai, Sakado, Saitama, 350-0295, Japan.
⁴ Graduate School of Material Science, Josai University, 1-1 Sakado, Saitama, 350-0295, Japan.
⁵ Department of Physics, Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto, 860-8555, Japan.
⁶ Institute of Industrial Nanomaterials (IINa), Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto, 860-8555, Japan.
⁷ School of Chemistry F11, The University of Sydney, Sydney, NSW 2006, Australia.

PMID: 34846768
DOI: 10.1002/chem.202103367

Abstract

Magnetoelectric (ME) materials exhibiting coupled electric and magnetic properties are of significant interest because of their potential use in memory storage devices, new sensors, or low-consumption devices. Herein, we report a new category of ME material that shows liquid crystal (LC), ferroelectric (FE), and field-induced single molecule magnet (SMM) behaviors. Co(II) complex incorporating alkyl chains of type [Co(3C₁₆ -bzimpy)₂ ](BF₄ )₂ (1; 3C₁₆ -bzimpy=2,2'-(4-hexadecyloxy-2,6-diyl)bis(1-hexadecyl-1H-benzo[d]imidazole)) displayed a chiral smectic C mesophase in the temperature range 321 K-458 K, in which distinct FE behavior was observed, with a remnant polarization (88.3 nC cm^-2 ). Complex 1 also exhibited field-induced slow magnetic relaxation behavior that reflects the large magnetic anisotropy of the Co(II) center. Furthermore, the dielectric property of 1 was able to be tuned by an external magnetic field occurring from both spin-lattice coupling and molecular orientational variation. Clearly, this multifunctional compound, combining LC, FE, and SMM properties, represents an entry to the development of a range of next-generation ME materials.

Keywords: cobalt(II) complexes; ferroelectricity; liquid crystal; magnetoelectric coupling; slow magnetic relaxation.

Grants and funding

JP17H01200/KAKENHI Grant-in-Aid for Scientific Research (A)