对激发状态内分子双质子转移行为的计算洞察力与Bis(2'-硫) 氨酸的原子电子负性相关
1College of Physical Science and Technology, Shenyang Normal University, Shenyang 110034, China.
Molecules (Basel, Switzerland)
|August 26, 2023
概括
这项研究探讨了新型 bis2'-硫) 基 (BBTHQ) 光体,揭示了较低的原子负电子度增强了结,并影响了兴奋状态质子转移 (ESPT) 机制.
科学领域:
- 摄影化学的使用.
- 光物理学的光学物理学
- 有机光体是有机光体的组成部分.
背景情况:
- 2-(2阿基) 班扎衍生物表现出独特的光化学和光物理特性.
- 新的bis(2阿基) 班扎衍生物 (BBTHQ) 因其光诱导的行为而被探索.
研究的目的:
- 研究具有不同原子电子负性的BBTHQ光体的照片诱导行为.
- 了解原子电子阴性,键和兴奋状态动态之间的关系.
- 阐明受原子电负性调节的兴奋状态双质子转移 (ESDPT) 的机制.
主要方法:
- 合成和表征BBTHQ-SO,BBTHQ-SS和BBTHQ-Se化合物.
- 红外 (IR) 光谱分析结构和振动变化.
- 模拟的核心-价值分支 (CVB) 索引来评估键.
- 构建潜在能量表面 (PESs) 来研究ESDPT路径.
主要成果:
- 低原子电子阴性增强了BBTHQ衍生物在S1状态下的双键.
- 特定的键 (BBTHQ-SO中的O4-H5N6和BBTHQ-SSe中的O1-H2N3) 在S1状态中得到加强.
- 在光激发后的电荷重组显示了有利的ESDPT趋势.
- 逐步揭示ESDPT行为和一个由原子电子负性调节的ESDPT机制.
结论:
- 原子电子阴性是调节BBTHQ光体中的键和ESDPT的一个关键因素.
- 这些发现为设计具有定制光化学性质的新型光体提供了洞察力.
- 这项工作建立了一个通过替代效应控制ESDPT的机制.
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