鉄 (II) 複合体における光誘発スピンクロスオーバーダイナミクスの5秒間のXANES研究
Ch Bressler1, C Milne, V-T Pham
1Ecole Polytechnique Fédérale de Lausanne, Laboratoire de Spectroscopie Ultrarapide, ISIC, FSB-BSP, CH-1015 Lausanne, Switzerland.
Science (New York, N.Y.)
|December 17, 2008
まとめ
超高速X線吸収スペクトロスコピーは,鉄 (III) トリス (III) ビピリジン) 複合体におけるクインテット状態の形成を追跡した. これは150フェムト秒のカスケードメカニズムを明らかにし,クインテット状態の人口動態を明らかにします.
科学分野:
- 化学物理 化学物理
- フォトケミストリー フォトケミストリー
- スペクトル顕微鏡検査です.
背景:
- X線吸収スペクトロスコーピー (XAS) は分子構造を調査する.
- 以前のXAS方法は,超高速ダイナミクスには遅すぎた.
- 鉄 (((II) 複合体は,複雑な興奮状態の行動を示します.
研究 の 目的:
- 水性鉄で超高速クインテット状態の形成を調査する (II) トリス (III) ビピリジン).
- フォトエキシテーション後のクインテット状態の人口の時間スケールを決定する.
- 鉄複合体におけるクインテット状態形成のメカニズムを解明する.
主な方法:
- フェムト秒光学ポンプ/X線探査機スペクトロスコピー.
- X線吸収近縁構造 (XANES) 分析.
- XANESの機能の監視は,時間の経過とともに遅延します.
主要な成果:
- クインテットの状態は,約150フェムト秒で満たされました.
- 300 fsで記録されたクインテット状態の完全なXANESスペクトル.
- 1MLCT → 3MLCT → 5Tカスケードメカニズムを特定しました.
結論:
- クインテット州の人口メカニズムに関する長年の問題を解決しました.
- 超高速ダイナミクスを追跡するXASの能力を実証しました.
- 3MLCT → 5TのリラクゼーションをFe-Nの振動周期にリンクした.
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