激发电荷转移复合物的快速放松的性质
1Department of Chemistry and Biochemistry, University of Maryland Baltimore County, Baltimore, Maryland 21250, USA.
Journal of the American Chemical Society
|August 26, 2004
概括
激发的电荷转移复合体可以形成接触激素离子对 (CRIP). 乙烯/TCNB复合体表现出独特的放松通路,与其他捐赠体不同,影响了电子转移理论.
科学领域:
- 摄影化学的使用.
- 化学物理 化学物理
- 电子转移是指电子的转移.
背景情况:
- 电荷转移 (CT) 复合体对于理解电子转移过程至关重要.
- 接触激素-离子对 (CRIP) 的形成是许多光化学反应中的关键中间步骤.
研究的目的:
- 研究来自激发CT复合体的CRIPs的形成和放松途径.
- 为了比较不同芳香捐助者的CRIP形成动态与1,2,4,5-四亚烯 (TCNB).
主要方法:
- 在1,2-二乙烯 (DCLE) 中对CT复合物的光谱分析 (吸收和排放).
- 时间分辨率的发射光谱学用于研究中间物种动态.
主要成果:
- 六甲基,五甲基和杜与TCNB的CT复合物显示镜像光谱,表明直接CRIP形成与轻微放松.
- 乙烯/TCNB复合体表现出不同的光谱和中间物种,这表明复杂的放松途径涉及电子变化.
- 乙烯/TCNB中间辐射频谱与其吸收频谱相匹配.
结论:
- CRIP的形成并不总是来自激发的CT复合体的直接过程.
- 乙烯/TCNB系统展示了一种放松路径,其中包括超越溶解和几何的电子重新排列.
- 这些发现对电子转移中的黄金规则表达式的有效性有影响.
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