一致的核动力学在超快的光诱导的结构变化 bis ((二胺) 铜 ((I) 复合体
Munetaka Iwamura1, Hidekazu Watanabe, Kunihiko Ishii
1Molecular Spectroscopy Laboratory, Advanced Science Institute (ASI), RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
Journal of the American Chemical Society
|April 29, 2011
概括
这项研究揭示了光刺激后铜复合体的超快速结构变化. 在激发状态下观察到一致的核运动,为分子动力学提供了洞察力.
科学领域:
- 摄影化学的使用.
- 超快速光谱法 超快速光谱法
- 计算化学计算化学
背景情况:
- 金属复合物在光激发时经历结构变化.
- 了解激发状态动态对于光化学至关重要.
研究的目的:
- 通过超快光谱学研究[Cu(dmphen) 2) ((+) 的光诱导结构变化.
- 阐明激发单元状态和系统间交叉的动态.
主要方法:
- 超快速光谱,时间分辨率为30 fs.
- 时间分辨率吸收测量.
- 时间依赖密度函数理论 (TDDFT) 的计算.
主要成果:
- 观察到明显的光谱变化,归因于单个激发状态中的D(2d) →D(2) 结构变化.
- 已确认的时间常数为结构变化时约0.8ps,系统间交叉时约10ps.
- 在激发状态中检测到连贯的核运动,表明一个明确的振动结构.
结论:
- 光刺激会诱导特定的振动模式,包括Cu-连接体键变化和连接体扭曲.
- 兴奋的单元状态在短时间内保持其结构和振动连贯性.
- 综合实验和计算方法提供了对光诱导动态的全面理解.
相关概念视频
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