在电子激发的六酸中溶剂介导电子定位的动力学 (III)
Wenkai Zhang1, Minbiao Ji, Zheng Sun
1PULSE Institute, SLAC National Accelerator Laboratory, Stanford University, Menlo Park, California 94025, USA.
Journal of the American Chemical Society
|January 12, 2012
概括
我们使用光谱学研究了激发Fe(CN) 6(3-) 中的电子孔定位. 最初的异位,洞局部化在二次激发状态,表明对称性变化.
科学领域:
- 摄影化学的使用.
- 频谱学是一种光谱学.
- 无机化学 无机化学 有机化学
背景情况:
- 在过渡金属复合体中,联到金属电荷转移 (LMCT) 激发至关重要.
- 了解激发状态动力学,包括电子孔定位,是控制反应性的关键.
研究的目的:
- 在LMCT激发后,研究激发状态Fe(CN) 6(3-) 中电子孔定位的动力学.
- 为了确定所涉及的兴奋状态的对称性和性质.
主要方法:
- 采用了极化分辨率的紫外线中红外探针光谱学.
- 进行了CN-stretch吸收带及其异质性的分析.
主要成果:
- 最初的LMCT激发状态表现出一个单一的CN-伸展带,没有异构性,表明非定位的连接体孔和保存的八面体对称性.
- 观察到具有两个CN伸展带的二次兴奋状态,这意味着较低的对称性.
- 二次状态的形成是依赖溶剂的.
结论:
- 最初分离的连接体孔定位在二次兴奋状态中.
- 这种局部化导致八面体对称性丧失.
- 这些发现提供了关于过渡金属复合体中兴奋状态动态和对称性破坏的见解.
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