Exploring proton-electron cooperative properties in bistable coordination compounds

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K05800
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Inorganic chemistry
• Research Institution: University of Tsukuba
• Principal Investigator: SHIGA Takuya 筑波大学, 数理物質系, 准教授 (00375411)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 双安定性 / 磁性 / プロトン / 電子 / 誘電性 / 分子エレクトロニクス / 鉄錯体 / 水素結合

Outline of Final Research Achievements

As for bistable molecules, which have multiple stable states, their various electronic states can be designed by modification of ligands and control of the structure of molecular assemblies. In this work, we aimed an achievement of control of permittivity by magnetic field and conversion of magnetism by electric field by the introduction of proton　responsive properties into bistable coordination complexes. An iron(II) mononuclear complex with asymmetric planar tridentate ligand with dissociative protons which have different pKa. Five kinds of iron complexes, which have different proton- and electronic states, were synthesized by trial-and-error of synthetic conditions, and their structures, magnetic properties, and electronic states were investigated.

Free Research Field

錯体化学

Academic Significance and Societal Importance of the Research Achievements

熱や光による物性変換は数多く報告されているが、プロトンに起因した双安定性の発現や電場応答性の研究は皆無であり、本研究の成果をもとに適切な分子選択・分子修飾を行うことで、プロトンの変位と連動した新しい外場応答性を持つ機能性分子材料を開発できると考えられる。これらの分子材料は、ナノサイエンス分野・分子エレクトロニクス分野におけるスイッチング素子や電子ペーパー、メモリ材料などへの応用が期待でき、近未来の高機能分子デバイス開発研究において重要な知見を与えるものと考えられる。