共有軌道:バッキー・フェロセネスとルテノセネスで異なる結果を持つ超高速の興奮状態の無活性化
Dirk M Guldi1, G M Aminur Rahman, Renata Marczak
1Universität Erlangen, Institute for Physical and Theoretical Chemistry, 91058 Erlangen, Germany. dirk.guldi@chemie.uni-erlangen.de
Journal of the American Chemical Society
|July 20, 2006
まとめ
バッキーのフェロセーヌ結合体は,有意な電荷移転を示し,転移安定した基幹イオンペアを形成する. バッキールテノセンの結合体は,より速い無効化と不利な酸化ポテンシャルにより,電荷の分離を示さない.
科学分野:
- フォトケミストリーとフォト物理学
- 有機金属化学 有機金属化学
- 超分子化学 超分子化学
背景:
- フルレレン-オルガノメタリック結合体は,それらの電子特性のために興味があります.
- フェロセーヌとルテノセーヌの誘導体は,異なる電子および酸化還元特性を持っています.
研究 の 目的:
- バッキー・フェロセンとバッキー・ルテノセンの結合体における基底と興奮状態の電子相互作用を調査する.
- 鉄とルテニウムを含むシステムの間の電荷伝送ダイナミクスと光物理的性質を比較する.
主な方法:
- 安定状態および時間解像度のある光スペクトロスコピーは,安定状態および時間解像度のある光スペクトロスコピーを用います.
- フェムト秒とナノ秒のポンプ・プローブ実験
- パルス放射溶解は,パルス放射溶解である.
主要な成果:
- バッキーのフェロセーヌ結合体は,フェロセーヌからフルレレンへの基礎状態の電荷密度の変化を大幅に示しています.
- バッキー・フェロセンの結合体の興奮状態は,急速な電荷分離 (0.8ps) を受け,ラジカルイオンペアを形成し,寿命は27-39psである.
- バッキールテノセンの結合体は電荷分離を示さないが,より重いルテニウム中心と不利な酸化可能性により,より速い興奮状態の無活性化 (~200 ps) が起こる.
結論:
- バッキー・フェロセンの密接な接触は,効率的な光誘発電子伝送を可能にします.
- ルテニウムの性質は,より重い性質と再酸化可能性を含め,バッキールテノセンの電荷分離を阻害し,急速な無効化につながります.
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