単一分子における導電性の切り替えは,形状の変化によるものです
Z J Donhauser1, B A Mantooth, K F Kelly
1Department of Chemistry, The Pennsylvania State University, University Park, PA 16802-6300, USA.
Science (New York, N.Y.)
|June 26, 2001
まとめ
フェニレン・エチニレン・オリゴマーの導電性スイッチングは,周囲のマトリックスに依存する. 順番が良いマトリクスはスイッチングの速度を低下させ,構造の変化がこの分子行動を誘導することを示唆しています.
科学分野:
- 分子電子 (モレキュラー・エレクトロニクス)
- 行動の切り替え現象
- オリゴマーのダイナミクス
背景:
- 分子スイッチングの理解は,高度な電子機器の開発に不可欠です.
- フェニレンエチニレンオリゴマーは,分子スイッチの有望な候補である.
- 周囲のマトリックスが分子行動に及ぼす影響は,十分に理解されていません.
研究 の 目的:
- 単一のフェニレンエチニレンオリゴーマーとバンドルされたフェニレンエチニレンオリゴーマーの導電性スイッチングダイナミクスを調査する.
- 分子スイッチングの持続性と速度に影響を与える要因を決定する.
- これらのオリゴマーの導電性スイッチングの背後にあるメカニズムを解明する.
主な方法:
- 孤立したオリゴーマーとバンドルされたオリゴーマーについて,経時的に追跡伝導性の切り替え.
- アルカンエチオラート単層を隔離マトリックスとして利用する.
- スイッチングの振る舞いを,周囲のマトリクスの順序と相関させる.
主要な成果:
- ON/OFF状態の持続時間は,数秒から数十時間まででした.
- 順番が良いマトリックスでは,順番が悪いマトリックスと比較して,スイッチング率が低かった.
- スイッチング周波数は,周りのマトリックスで秩序が低い場合よりも高かった.
結論:
- 分子スイッチングは,主にオリゴーマーまたはバンドルの構成の変化によって引き起こされます.
- 充電移転の静電効果は,スイッチングの主な原因である可能性は低い.
- 分子環境は,分子スイッチの安定性とダイナミクスに大きな影響を与えます.
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