塩化過渡金属複合体におけるフォト誘発のスピン状態変換は,時間解像度ソフトX線スペクトロスコピーを用いて探査された
Nils Huse1, Tae Kyu Kim, Lindsey Jamula
1Ultrafast X-ray Science Lab, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA. nhuse@lbl.gov
Journal of the American Chemical Society
|April 30, 2010
まとめ
鉄の複合体における光誘発スピンクロスオーバーは,X線スペクトロスコピーを用いて観察された. この研究は,超高速で高スピン状態への移行中に電子構造と結合長さの変化を明らかにしています.
科学分野:
- フォトケミストリー フォトケミストリー
- 無機化学 無機化学とは
- スペクトロスコーピーは,スペクトロスコーピーを用います.
背景:
- 鉄 (((II) ポリピリジル複合体は,スピンクロスオーバー現象を示す.
- スピン・クロスオーバーのダイナミクスを理解することは,分子電子学と触媒学にとって極めて重要です.
研究 の 目的:
- [Fe(tren(py) ((3)) ]^2+における溶液相光誘導スピンクロスオーバーを調査する.
- 低スピンから高スピンへの移行中の電子と構造の変化を時間解像度スペクトロスコーピーを用いて解明する.
主な方法:
- ピコ秒ソフトX線吸収スペクトロスコーピー.
- チャージ・トランスファー・マルチプレート計算.
- 低スピンと高スピンモデル複合体の研究.
主要な成果:
- 低スピン (1A1) から高スピン (5T2) 状態への光誘発変換を観察した.
- 高スピン状態でのリガンドフィールド分裂の ~ 1 eV の減少を測定しました.
- 直接観測されたFe-3d/N-2pの軌道重複の減少は,Fe-N結合の長さの増加と一致する.
結論:
- スピン・クロスオーバーは,シグマドネーションの減少を伴うが,弱体化されたPIバックボンドによって補償される.
- 時間分解の柔らかいX線吸収スペクトロスコピーは,超高速液相光化学反応の研究に有効です.
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