交互結合ブリッジを用いたドナー・ブリッジ・アクセプター分子における電子の移転を制御する
Annie Butler Ricks1, Gemma C Solomon, Michael T Colvin
1Department of Chemistry and Argonne-Northwestern Solar Energy Research Center, Northwestern University, Evanston, Illinois 60208-3113, United States.
Journal of the American Chemical Society
|October 15, 2010
まとめ
光誘発電荷分離 (CS) は,線形に比べ,交互結合ブリッジを通して著しく遅く,シグマ経路へのシフトを示唆しています. これは,ドナー・ブリッジ・アクセプター分子における電子伝送ダイナミクスに影響を与える.
科学分野:
- フォトケミストリー フォトケミストリー
- 分子電子 (モレキュラー・エレクトロニクス)
- 有機化学 オーガニック・ケミストリー
背景:
- ドナー・ブリッジ・アクセプター (D-B-A) 分子は,電荷分離 (CS) と再結合 (CR) を理解するために極めて重要です.
- ブリッジの電子特性は,CSおよびCRプロセスの効率に大きく影響します.
研究 の 目的:
- 異なるブリッジ結合 (クロス結合,線形結合,飽和) を有するD-B-A分子における光誘導CSとCRを比較および対比する.
- 電子伝送率と電子結合におけるブリッジ構造の役割を調査する.
主な方法:
- 時間解像度スペクトロスコピーは,CSとCRの動態を研究するために使用されました.
- トゥルーブリッジ電子結合を分析するために分子伝導率の計算を行った.
主要な成果:
- 交互結合した1,1-ジフェニルエーテンのブリッジを通過するCSは,飽和ジフェニルメタンブリッジと比較できる線形トランススティルベンの同位体を通過するよりも30倍遅かった.
- 交互結合のキサントンブリッジを通過したCSは,その線形トランススティルベンの同位体と同様の割合を示しました.
- 分子伝導率の計算により,交互結合系における量子干渉効果が明らかになり,電子結合が変化した.
結論:
- 交叉結合は,ドナー-受容器電子結合へのpi軌道貢献を大幅に減らし,CSのシグマ経路を好む.
- 交互結合ブリッジにおける量子干渉効果は,電子結合を調節し,実験的な電子伝送速度の動向に合わせます.
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