围绕光激发的水性化物周围超快速溶解过程的实时结构动态
Verena Markmann1, Jaysree Pan1, Bianca L Hansen1
1Technical University of Denmark Anker Engelunds Vej 1 2800 Lyngby Denmark vmark@dtu.dk.
Chemical science
|July 26, 2024
概括
从化离子中对电子的光抽象触发了溶剂外在素原子周围的重组,在几秒钟内完成. 随后的电子-素重组发生在双重时间尺度上,由扩散电子弹射解释.
科学领域:
- 物理化学 物理化学
- 摄影化学的使用.
- 解决方案动力学 解决方案动力学
背景情况:
- 电荷转移到溶剂的过程涉及从溶液中的离子中抛出电子.
- 了解溶剂重组动态对于反应机制至关重要.
研究的目的:
- 从化物 (I-) 和化物 (Br-) 离子进行电子光抽象后研究结构动力学.
- 实时描述溶剂的扩张和重组情况.
- 量化新生中性物种与周围水分子之间的相互作用.
主要方法:
- 利用时间解析的X射线溶液散射 (TR-XSS) 来探测结构变化.
- 在202nm和400nm使用单光子和2光子激发.
- 分析散射数据以评估竞争的相互作用模型.
主要成果:
- 观察到光刺激后结构重组的0.1ps延迟.
- 解决方案重组在0.5-1ps内完成.
- 确定了I0:e-重组的两个不同的时间表 (∼20ps和100s的ps).
结论:
- 溶剂重组动态与化离子的电子弹出直接相关.
- 电子离子重组是由扩散喷射距离控制的.
- TR-XSS提供了对溶液中的超快速化学过程的实时洞察.
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