A Ferroelectric Metallomesogen Exhibiting Field-Induced Slow Magnetic Relaxation.

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 single molecule magnet (SMM) behaviors. Co(II) complex incorporating alkyl chains of type [Co(3C16-bzimpy) 2 ](BF 4 ) 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 ). 1 also exhibited field-induced slow magnetic relaxation behavior that reflects the large magnetic anisotropy of the Co(II) center. Furthermore, 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.