在双键中心沙利西甲基亚中进行质子合异构化
Ye Wang1, Dongdong Wang1, Song Zhang1
1State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy
|September 2, 2023
概括
在甲亚 (SAA) 中,激发状态内分子质子转移 (ESIPT) 发生在200 femtosecond以下. 溶剂的极性影响了这些光色分子中的质子转移动态,振动放松和异构.
科学领域:
- 摄影化学的使用.
- 分子动力学分子动力学
- 超分子化学 超分子化学
背景情况:
- 希夫基地中的质子转移动态对于潜在的应用至关重要.
- 像甲亚 (SAA) 这样的光色材料表现出有趣的光诱导转变.
- 了解激发状态的分子内质子转移 (ESIPT) 是设计高级功能分子的关键.
研究的目的:
- 为了研究甲亚 (SAA) 在溶液中的激发状态内分子质子转移 (ESIPT) 动态.
- 阐明质子转移,振动放松和异构化过程的时间演变.
- 为了确定溶剂极性对这些超快分子事件的影响.
主要方法:
- 时间分辨率光谱,包括暂时吸收和刺激发射.
- 计算化学方法用于理论分析.
- 溶剂极性变化的研究.
主要成果:
- 在400nm光刺激下观察到两个不同的光谱波段.
- 发现ESIPT过程发生在200 femtosecond (fs) 之内.
- 随后的振动放松发生在皮秒 (ps) 时间尺度上,随后在几十个皮秒的时间尺度上发生异体化,溶剂极性显著影响了这些动态.
结论:
- 在SAA中,单个质子转移而不是双重质子转移.
- 观察到的纳秒级放松成分归因于以诺结构的放松.
- 这些发现提供了关于光色希夫基中超快质子转移机制的见解.
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