快速な分子内電荷移転は,平面的な硬化電子ドナー/受容分子によるものです
Toshitada Yoshihara1, Sergey I Druzhinin, Klaas A Zachariasse
1Max-Planck-Institut für biophysikalische Chemie, Spektroskopie und Photochemische Kinetik, 37070 Göttingen, Germany.
Journal of the American Chemical Society
|July 9, 2004
まとめ
平面性フルオロゼネ (FPP) は,興奮状態では素早い分子内電荷移転 (ICT) を示しています. 効率的なICTは,大きな分子運動を必要とせず,高速スイッチングシステムの設計に関する以前の仮定に異議を唱える.
科学分野:
- フォトケミストリー フォトケミストリー
- 分子ダイナミクス 分子ダイナミクス
- オーガニック化学 オーガニック化学
背景:
- 分子内電荷伝送 (ICT) は,基本的な光物理学的プロセスである.
- 急速なスイッチングのための分子を設計するには,ICTのダイナミクスを理解する必要があります.
- 歪んだ内分子電荷移転 (TICT) 状態は,しばしば重要な分子再配置を含みます.
研究 の 目的:
- 平面分子フローラゼネ (FPP) の興奮状態ダイナミクスを調査する.
- 効率的なICTが,大きな振幅の動きのない平面系で発生できるかどうかを判断する.
- FPPのICT動作を,その柔軟なアナログであるN-フェニルピロール (PP) と比較する.
主な方法:
- 興奮状態のダイナミクスを研究するための時間解像度スペクトロスコピー.
- 溶媒の極性研究で,電荷移転特性を探知する.
- 異なる電子状態に対する二極電極モメントの計算.
主要な成果:
- フロロラゼネ (FPP) は, -45°Cのエチルシアン化物における迅速 (12 ps) の可逆性ICTを実証しています.
- FPPのICT状態は,局所的に刺激された状態 (1D) よりもはるかに高い大きな二極電極モメント (13D) を有しています.
- FPPのICTの振る舞いは,柔軟なN-フェニルピロール (PP) の振る舞いをよく反映しており,平面構造における効率的な電荷移転を示しています.
結論:
- 平面的な興奮状態への効率的な分子内電荷移転は達成可能である.
- 迅速に切り替えられるICTシステムを設計するには,TICT状態を形成する TICT状態のような大きな分子運動は必要ありません.
- 平面的硬化分子は,効率的かつ迅速なICTシステムを開発するための実行可能なプラットフォームを提供します.
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