対称性が禁止された興奮四極結合状態の観測
Yuan Liu1, Guo-Zhu Zhu1, Dao-Fu Yuan1
1Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States.
Journal of the American Chemical Society
|November 13, 2020
まとめ
我々は,テトラシアノベンゼンアニオン (TCNB−) で希少な対称性禁止興奮四極結合状態 (QBS) を観測した. この発見は,アニオンスペクトロスコーピーの伝統的な選択規則に挑戦しています.
科学分野:
- 化学物理学
- 分子光譜法
- 量子化学について
背景:
- アニオン光譜は電子-分子相互作用の洞察を提供します.
- 非値状態を理解することは,電子-リガンドの相互作用にとって極めて重要です.
- シンメトリー選択の規則は分子システムにおける移行を統制する.
研究 の 目的:
- テトラシアノベンゼンアニオン (TCNB−) の対称性禁止興奮四極結合状態 (QBS) を観察し,特徴づけること.
- TCNBとQBSの結合エネルギーを正確に測定する.
- 非バレンスの状態へのビブロニックの移行における対称性の選択規則の役割を調査する.
主な方法:
- 低温冷却されたTCNB−の光電子スペクトロスコーピー.
- 低温冷却されたTCNB−の光解離スペクトロスコーピー.
- バイブロニックの移行と選択規則の分析
主要な成果:
- TCNB−における対称性禁止興奮四極結合状態 (QBS) の観測.
- TCNB電子親和 (2.4695 eV) とQBS結合エネルギー (0.2206 eV) の正確な測定
- QBSへの振動的移行の識別は,地面の振動状態が禁止されています.
結論:
- フランク・コンドン原理ではなく シンメトリー選択の法則が バイブロニクスの移行を制御しています
- QBSの大きな結合エネルギーは,強い相関と極化効果に起因する.
- この研究は,アニオンにおける非価値状態への対称性による変遷の希少な例を示している.
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