在1,8-二氧化纳乙烯-2,7-二甲中逐步激发状态的分子内双质子转移
Diksha Pandey1, Sivaranjana Reddy Vennapusa1
1School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Maruthamala P. O., Vithura, Thiruvananthapuram 695551, Kerala, India.
The journal of physical chemistry. A
|July 5, 2024
概括
这项研究探讨了DHDA中激发状态的分子内双质子转移. 模拟显示质子转移发生在S1状态,导致双光辐射.
科学领域:
- 摄影化学的使用.
- 理论化学 理论化学
- 分子动力学分子动力学
背景情况:
- 激发状态内分子双质子转移 (ESIDPT) 是光化学中的一个关键过程.
- 了解ESIDPT机制是设计新型光响应材料的关键.
研究的目的:
- 从理论上研究1,8-二氧纳-2,7-二甲 (DHDA) 中逐步激发状态的分子内双质子转移 (ESIDPT).
- 阐明单个和双个质子转移事件的动态和时间尺度.
- 为了探索 tautomer 稳定性和光发射之间的关系.
主要方法:
- 使用了表面轨迹模拟.
- 采用了依赖时间的密度函数理论 (TD-B3LYP),使用了6-31G(d) 基础集.
- 分析了质子转移路径和时间尺度.
主要成果:
- 质子转移主要发生在S1兴奋状态中.
- 大约42%的轨迹表现出单个质子转移 (平均时间~147 fs).
- 在~32%的轨迹中观察到双质子转移,第一步平均为~54 fs,第二步平均为~151 fs.
- 这三种分离体 (正常,单质和双质子转移) 都在S1状态下显示稳定的最小值.
- S1状态表现为 ππ* 字符,导致双光发射.
结论:
- DHDA主要通过S1状态逐步经历ESIDPT.
- 在S1状态下观察到的体稳定性和ππ*特征解释了双光发射现象.
- 这项研究为DHDA和相关分子的光物理行为提供了洞察力.
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