在一个非中心对称的电子捐赠-接受-捐赠分子中激发状态对称性破坏和定位
Bogdan Dereka1, Evangelos Balanikas2, Arnulf Rosspeintner2
1Department of Chemistry, University of Zurich, CH-8057 Zurich, Switzerland.
The journal of physical chemistry letters
|August 15, 2024
概括
在曲的分子中,激发状态对称性破坏 (ES-SB) 显示在极性溶剂中共存的局部和非局部激发. 与中心对称分子相比,不可逆转的局部化需要更高的溶剂极性.
科学领域:
- 摄影化学的使用.
- 分子光谱学 分子光谱学
- 有机化学 有机化学
背景情况:
- 四极联分子中的电子激发通常在极地环境中的捐赠者-接受者 (DA) 分支上定位.
- 激发状态对称性破坏 (ES-SB) 会导致反转中心的损失,从而改变了红外和拉曼光谱的振动过渡规则.
研究的目的:
- 为了比较ES-SB在一个直角 (曲) DAD染料 (1) 和一个中心对称的 DAD染料 (2).
- 研究分子几何学和扭曲障碍对极性溶剂激发局部化的影响.
主要方法:
- 时间分辨率红外 (IR) 光谱法用于监测ES-SB.
- 在曲分子 (1) 和中心对称分子 (2) 之间比较ES-SB动态.
主要成果:
- 在曲分子 (1) 中观察到刺激局部化,类似于中心对称分子 (2).
- 对于分子 (1),具有局部和非局部激发的子群共存在弱中极溶剂中,与分子 (2) 不一样.
- 分子激发状态中的扭曲障碍 (1) 解释了局部化和非局部化状态的共存.
结论:
- 曲分子表现出ES-SB,可以观察到激发局部化.
- 分子几何学和兴奋状态扭转障碍显著影响局部和非局部兴奋状态的共存.
- 在曲分子中不可逆转的激发局部化需要比中心对称对应物更高的溶剂极性.
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