在 (Cp) 2Ti (IV) (NCS) 2中,非局部联体到金属电荷转移激发状态的非局部联体
Elizabeth L Patrick1, Chad J Ray, Grant D Meyer
1Department of Chemistry, The University of New Mexico, Albuquerque, New Mexico 87131, USA.
Journal of the American Chemical Society
|May 2, 2003
概括
这项研究揭示了金属中强烈的光, (Cp) 2Ti(NCS) 2,从一个联体到金属的电荷转移三重组激发状态. 时间分辨率红外光谱学证实了这种激发状态的非局部性质,而不会破坏对称性.
科学领域:
- 协调化学 协调化学
- 光物理学的光学物理学
- 频谱学是一种光谱学.
背景情况:
- 金属是多功能化合物,在催化和材料科学中具有应用.
- 合体到金属电荷转移 (LMCT) 激发状态对于理解协调复合体中的光物理过程至关重要.
- 来自LMCT状态的光在d(0) 金属中是相对未被探索的.
研究的目的:
- 为了研究曲d(0) 金属的光物理性质, (Cp) 2Ti ((NCS) 2.
- 用光谱和计算方法来表征连接物到金属的电荷转移三重组激发状态.
- 为了探索激发状态的动态,使用时间分辨率红外光谱在冷温度下.
主要方法:
- 在有机玻璃和PMMA基板中低温 (77K) 光谱学.
- 量子化学计算 (DFT) 来确定轨道亲属和电子结构.
- 低温 (77K) 时间分辨率红外光谱 (TRIR) 在纳秒时间尺度上.
- 对TRIR数据的单值分解 (SVD) 分析.
主要成果:
- 从LMCT三组激发状态的 (Cp) 2Ti ((NCS) 2) 在77K时观察到强烈的光.
- TRIR光谱学揭示了CN伸展区域的短暂的红外波段,与三重激发状态相对应.
- 分析表明,非局部化的LMCT激发状态没有显著的对称性破坏,得到计算和实验数据的支持.
结论:
- 该研究提供了第一个在d(0) 金属中LMCT激发状态的时间分辨率红外探测.
- 这些发现表明,LMCT三重激发状态在两个NCS ((-)) 连接体中都脱局.
- 薄膜基板中的冷TRIR光谱是一种强大的工具,用于表征过渡激发状态.
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