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Updated: Jun 29, 2026
10:52
Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
环烯和环烯-d10在200nm激发时的超快动态
W Fuss1, W E Schmid, S A Trushin
1Max-Planck-Institut für Quantenoptik, D-85741 Garching, Germany.
Journal of the American Chemical Society
|July 19, 2001
概括
使用紫外线激发环素,显示出超快的动态. 化只影响一个时间常数,这表明在碳形成之前, [1,3]-sigmatropic转移到激发状态.
科学领域:
- 物理化学 物理化学
- 摄影化学的使用.
- 化学动力学 化学动力学
背景情况:
- 了解环烯光化学的超快动态对于阐明反应机制至关重要.
- 之前的研究已经确定了环甲基作为一个关键的光化学产品.
研究的目的:
- 为了研究紫外线激发后的环烯的时间解析动态.
- 为了识别卷入环烯光化学中的过渡中间体和反应途径.
主要方法:
- 在200nm时对环烯的气相激发.
- 非共振多光子电离探测与质量选择性检测.
- 时间分辨率测量,使用femtosecond分辨率.
- 化研究是为了探测反应机制.
主要成果:
- 观察了四个不同的时间常数 (20,47,43,350 fs),分配给不同的激发状态和基本状态过程.
- 化显著改变了47 fs时间常数,表明了的转移.
- 观察到,碳烯的形成始于激发状态,并在基本状态继续.
结论:
- 观察到的动态表明,最初从弗兰克-康登区域偏离,然后在pipi*兴奋状态上发生[1,3]-sigmatropic转移.
- 碳化合物形成始于激发状态,并继续在基态,随后发生C-C键转移和异构.
- 碎片化模式表明,布他的形成和反复-迪尔斯-阿尔德反应发生在更长的时间尺度上.
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