Akiyoshi Ryohei, Hayami Shinya
Department of Chemistry, School of Science, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan.
Department of Chemistry, Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto 860-8555, Japan.
Chem Commun (Camb). 2022 Jul 26;58(60):8309-8321. doi: 10.1039/d2cc02484e.
Ferroelectrics that display electrically invertible polarisation are attractive materials because of their potential for wide-ranging applications. To date, considerable effort has thus been devoted towards developing ferroelectric materials, particularly those comprising organic/inorganic compounds. In these systems, structural dynamics such as atomic displacement and reorientation of polar ions/molecules play a key role in the generation of reversible spontaneous polarisation. Although there are many reports concerned with organic/inorganic ferroelectrics, ferroelectrics based on coordination metal complexes have been largely unexplored despite their often unique electronic and spin state properties. In this feature article, we discuss recent progress involving coordination metal complex-based ferroelectrics where the reversible polarisation originates not only from structural dynamics (represented by proton transfer, molecular motion, and liquid crystalline behaviour) but also from electron dynamics (represented by electron transfer and spin crossover phenomena) occurring at the metal centre. Furthermore, unique synergy effects ( magnetoelectric coupling) resulting from the structural and electron dynamics are described. We believe that this review pertaining to ferroelectric coordination metal complexes provides new insights for fabricating further advanced functional materials such as multiferroics and spintronics.
具有电可逆极化的铁电体因其具有广泛应用潜力而成为有吸引力的材料。迄今为止，人们在开发铁电材料方面投入了大量精力，特别是那些由有机/无机化合物组成的材料。在这些体系中，诸如原子位移和极性离子/分子的重新取向等结构动力学在可逆自发极化的产生中起着关键作用。尽管有许多关于有机/无机铁电体的报道，但基于配位金属配合物的铁电体尽管通常具有独特的电子和自旋态性质，却在很大程度上未被探索。在这篇专题文章中，我们讨论了基于配位金属配合物的铁电体的最新进展，其中可逆极化不仅源于结构动力学（以质子转移、分子运动和液晶行为为代表），还源于在金属中心发生的电子动力学（以电子转移和自旋交叉现象为代表）。此外，还描述了由结构和电子动力学产生的独特协同效应（磁电耦合）。我们相信，这篇关于铁电配位金属配合物的综述为制造诸如多铁性材料和自旋电子学等更先进的功能材料提供了新的见解。
