Development of external-field-responsive conductors based on TTF derivatives containing heterocycles

2021 Fiscal Year Final Research Report

• Project/Area Number: 18K05264
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 35030:Organic functional materials-related
• Research Institution: Osaka Prefecture University
• Principal Investigator: Fujiwara Hideki 大阪府立大学, 理学(系)研究科(研究院), 教授 (70290898)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: 有機伝導体 / 伝導性 / 磁性 / πーｄ相互作用 / TTF / 複素環 / X線構造解析 / 光機能性

Outline of Final Research Achievements

Various TTF derivatives containing heterocycles such as 1,3,4-thiadiazole, pyridine, pyrazine, and pyrimidine were synthesized in which the nitrogen atom of the heterocycles can strongly coordinate to the magnetic metal atom. We have prepared their various cation radical salts and cleared their crystal structures and conductivity / magnetic properties, especially the interaction with magnetic transition metal anions. We also developed extended TTF derivatives with a diazaquinoid skeleton and clarified their crystal structures and optical and electronic properties. In particular, it was clarified that this molecule has an electrochromic characteristic that shows a vivid color change depending on the applied electric field. Furthermore, we have revealed the expression of fluorescence by the introduction of nitrogen atom, and the aggregation-induced emission behavior.

Free Research Field

物性化学

Academic Significance and Societal Importance of the Research Achievements

本研究において、①複素環を有する各種ドナー分子を用いた新たな伝導性塩の開発に成功し、その構造と電気的・磁気的物性に関する知見を得た、②溶媒極性の変化によって互変異性を誘起し、その電子供与性や光機能性が大きく変化するドナー分子の開発に成功した、③複素環の導入により顕著なエレクトロクロミック挙動を示す拡張型TTF誘導体の開発に成功し、さらに低温における強い蛍光発光の誘起も見出した。本研究を通じて得られた複素環を有するドナー分子の各種機能性に関する成果は、外場応答性を示す有機材料の今後の研究開発に向けた有益な知見となったと考えられる。