素对激发状态分子间质子转移反应的替代效应
Hiroki Oyama1, Yoshinobu Nishimura2
1Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki, 305-8571, Japan.
概括
光尿素化合物的替代物会影响激发状态分子间质子转移 (ESPT) 反应. 这项研究表明,特定的化学修饰如何可以控制这些系统中的双光辐射.
科学领域:
- 摄影化学的使用.
- 超分子化学 超分子化学
- 有机化学 有机化学
背景情况:
- 光芳香尿素化合物通过激发状态的分子间质子转移 (ESPT) 在酸盐离子的存在下表现出双重光.
- 在ESPT过程中,从激发复合体 (N*) 中形成激发性复合体 (T*).
研究的目的:
- 研究替代剂 (-CF3, -F, -Cl) 对甲基-1-yl-3-phenylurea衍生物中基的p位置的影响.
- 分析这些替代剂如何影响ESPT反应动力学和N*和T*状态的失活路径.
- 确定替代品电子特性对反向ESPT速率常数 (k-PT) 的影响.
主要方法:
- 对替代的炭-1-yl-3-phenylurea衍生物进行了光谱测量.
- 动力分析被用来评估ESPT反应的速率常数.
- 考虑了替代效应的计算估计 (例如, -I 和 +Iπ 效应).
主要成果:
- 发现反向ESPT速率常数 (k-PT) 取决于特定的替代物.
- 替代剂在激发状态下从T*到N*对逆ESPT过程产生差异影响.
- 替代物 (-F) 呈现出潜在的轻微电子捐赠特性,影响了反向过程.
结论:
- 替代品选择提供了一种方法来控制ESPT系统的排放特性.
- 了解替代物效应对于设计具有定制光物理行为的光材料至关重要.
- 这项研究提供了通过向化学修饰来调节双光的见解.
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