硫黄ベースの分子内水素結合:興奮状態の水素結合オン/オフスイッチと二重室温の光

Zong-Ying Liu¹, Jiun-Wei Hu², Chun-Hao Huang³

¹Department of Chemistry , National Taiwan University , Taipei , 10617 Taiwan , Republic of China.

Journal of the American Chemical Society

|June 28, 2019

まとめ

この研究は,室温の光を用いたチオン分子における興奮状態の水素結合のオン/オフ反応を明らかにした. この"分子ワイパー"メカニズムは二重光を説明し,水素結合化学の新たな道を開く.

科学分野:

写真化学
超分子化学
材料科学

背景:

水素結合 (H結合) は分子相互作用において極めて重要です.
H結合の興奮状態のダイナミクスを理解することは,分子機能を制御する鍵です.
室温の光 (RTP) は,興奮状態のプロセスに敏感な探査機を提供します.

研究の目的:

O−H−S 結合の形成と興奮状態のダイナミクスを研究する.
特定のチオン分子で観察された異常な二重RTPの背後にあるメカニズムを解明する.
新しい刺激状態の分子内H結合のオン/オフ反応を証明する

主な方法:

室温の光光学 (RTP) を利用した.
7-hydroxy-2,2-dimethyl-2,3-dihydro-1 H-indene-1-thione (DM-7HIT) の光物理的性質について調査した.
S1 と T1 状態,システム間交差,内部変換を含む興奮状態経路を分析した.

主要な成果:

DM-7HITで550nmと685nmで異常な二重RTP放射を観測した.
"分子ワイパー"と呼ばれる刺激状態の分子内H結合のオン/オフスイッチングメカニズムを明らかにした.
トリプル状態 (T1とT1) の間の予備均衡を確立し,二重排出を駆動する.

結論:

この研究は,刺激状態での新しいH結合スイッチングメカニズムを示しています.
この発見は,H結合システムの光化学に関する基本的な洞察を提供します.
この研究は,調節可能な光物理的性質を持つ分子を設計するための新しい可能性を開きます.

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