替代对和类的S1放松动态的影响
1Department of Chemistry, KAIST, Daejeon 34141, Republic of Korea.
The journal of physical chemistry. A
|December 4, 2024
概括
二和二的动态揭示了能量依赖的放松通路. 替代影响内部转换和C-Cl键解离,影响激发状态的寿命.
科学领域:
- 物理化学 物理化学
- 分子光谱学 分子光谱学
- 摄影化学的使用.
背景情况:
- 了解兴奋状态动态对于预测分子行为至关重要.
- 芳香化合物表现出由电子结构影响的复杂放松通路.
- 内分子结和溶剂相互作用显著影响分子动力学.
研究的目的:
- 为了研究二 (CB) 和二 (3-CP,2-CP) 以及它们的水添加物的S1状态放松动态.
- 阐明内部转换和C-Cl键解离在激发状态放松中的作用.
- 探索替代和结对超快S1放松的影响.
主要方法:
- 用皮科秒时间分辨率的探针光谱法用于州特定的调查.
- 能量依赖测量允许分析放松率作为内部能量函数的分析.
- 对CB,3-CP,3-CP·H2O和2-CP·H2O的比较研究提供了对替代剂和结合效应的见解.
主要成果:
- 二通过低能量的内部转化和高能量的C-Cl键解离 (>2000 cm-1) 呈现放松作用.
- 3-二醇表现出类似的能量依赖放松,其中内部转化是主要的途径.
- 水添加物 (3-CP·H2O,2-CP·H2O) 突出了构造结构和分子内键在S1放松动态中的重要作用.
结论:
- 替代促进S1/S0内部转换,通过影响形交叉点的能量位置.
- 形交叉点S1 ((ππ*) /πσCCl*具有动态作用,特别是在由于O-H···Cl结合而导致的2-二中.
- 形态动力学和分子内结合是控制醇-水复合物的超快兴奋状态放松的关键因素.
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