超高速光誘導によるビス ((ダイミン) 銅 ((I) 複合体の構造変化における一貫した核動力学
Munetaka Iwamura1, Hidekazu Watanabe, Kunihiko Ishii
1Molecular Spectroscopy Laboratory, Advanced Science Institute (ASI), RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
Journal of the American Chemical Society
|April 29, 2011
まとめ
この研究では,光刺激によって銅複合体の超高速構造変化が明らかになりました. 興奮状態における一貫した核運動が観察され,分子動力学への洞察を提供した.
科学分野:
- フォトケミストリーは,写真化学です.
- 超高速スペクトル顕微鏡
- コンピューティング・ケミストリー
背景:
- 金属複合体は,光刺激によって構造変化を起こします.
- 興奮状態のダイナミクスを理解することは,光化学にとって極めて重要です.
研究 の 目的:
- 超高速スペクトロスコーピーを用いて[Cu(dmphen) 2) (((+) の光誘導による構造変化を調査する.
- 刺激されたシングレット状態とシステム間の交差のダイナミクスを解明する.
主な方法:
- 30fsの時間解像度を持つ超高速スペクトルスコピー.
- 時間分解の吸収測定.
- 時間依存密度関数理論 (TDDFT) の計算.
主要な成果:
- シングレット興奮状態の構造変化D(2d) →D(2) に起因する明確なスペクトル変化が観察されました.
- 構造変化の場合は ~0.8 ps,システム間交差の場合は ~10 psの確認された時間常数.
- 興奮状態で一貫した核運動を検知し,よく定義された振動構造を示した.
結論:
- 光刺激は,Cu-リガンド結合の変化やリガンドの回転を含む特定の振動モードを誘発します.
- 興奮したシングレット状態は,その構造と振動的相関性を短期間維持する.
- 組み合わせた実験的および計算的アプローチは,光誘導ダイナミクスの包括的な理解を提供します.
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