Investigation on the property of the single pi-systems

2018 Fiscal Year Final Research Report

• Project Area: pi-System Figuration: Control of Electron and Structural Dynamism for Innovative Functions
• Project/Area Number: 26102013
• Research Category: Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
• Allocation Type: Single-year Grants
• Review Section: Science and Engineering
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: Kiguchi Manabu 東京工業大学, 理学院, 教授 (70313020)
• Co-Investigator(Kenkyū-buntansha): 藤井 慎太郎 東京工業大学, 理工学研究科, 特任准教授 (70422558)
• Project Period (FY): 2014-07-10 – 2019-03-31
• Keywords: π分子 / 単分子接合

Outline of Final Research Achievements

We investigated the electron transport and thermal transport property of the single molecule junctions of the pi molecules. For example, we were able to fabricate the highly-conducting molecular circuits based on antiaromaticity. We measured the electron transport property of antiaromatic norcorrole-based Ni(II) complex (Ni(nor)) and porphyrin-based aromatic counterpart (Ni(porph)) using scanning electron microscope (STM). As a result, the electron transport property of Ni(nor) was drastically improved compared with Ni(porph). Single-molecule current voltage measurements and ab initio transport calculations reveal that this results from a reduced energy gap and a frontier molecular resonance closer to the Fermi level in the antiaromatic species. The conductance of the antiaromatic complex is further modulated electrochemically, demonstrating its potential as a high-conductance transistor.

Free Research Field

機能物性化学

Academic Significance and Societal Importance of the Research Achievements

本研究では単一π造形分子の電気伝導特性と熱電特性の解明及び、単一π造形分子の物性制御に成功した。例えばπ造形分子の特性を用いる事に従来よりもはるかに高い電気伝導性を示す単分子回路の作製に成功した。また、単一π造形分子に機械的な応力を加えることで反応障壁を減少させ反応を誘起させることに成功した。本研究により発見された単一π造形分子の物性は新たな分子素子の創製や反応場の設計に役立つ知見である。