電子移転反応の反応座標に沿った振動変相

Yusuke Yoneda¹, Bryan Kudisch², Shahnawaz R. Rather²

¹Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan.

Journal of the American Chemical Society

|September 3, 2021

まとめ

分子振動は,光誘導電子移転 (ET) 反応において重要な役割を果たします. この研究では,反応座標に結合された振動は,ET率が増加するにつれて,より早くコヘランスを失っていることが示されています.

科学分野:

物理化学
化学物理学
スペクトロスコーピー

背景:

光誘導電子移転 (ET) 反応における分子振動の役割は,現在進行中の科学的議論の対象となっている.
振動のダイナミクスを理解することは,反応メカニズムの解明に不可欠です.

研究の目的:

電子転送システムの振動波パケットダイナミクスを調査する.
振動コヒーレンスと電子伝送率の関係を決定する.

主な方法:

10フェムト秒未満のレーザーパルスによるブロードバンドポンププローブ (BBPP) スペクトロスコーピー.
逆フーリエフィルタリングを用いたコヒーレントの振動波パケット (170×1600 cm−1) の分析.
Huang-Rhys因子を決定するための密度関数理論 (DFT) の計算.

主要な成果:

ナフタセンの染料/溶媒システムで観測された一貫した振動波パケット.
振動的コヒーレンスの一部の変相時間は,ET率の増加とともに減少することを発見しました.
ET反応座標と結合した大きなHuang-Rhys因子を持つ振動モードを特定した.

結論:

特定の振動モードでの相相相合性の喪失は,電子移転反応座標への結合を示します.
振動ダイナミクスは,光誘発電子移転反応の動力学に大きな影響を与える.

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