在中观察到的过渡状态和非线性激发,使用sub-5 fs脉冲激光
Izumi Iwakura1, Atsushi Yabushita, Takayoshi Kobayashi
1Department of Applied Physics and Chemistry and Institute for Laser Science, University of Electro-Communications, 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585, Japan.
Journal of the American Chemical Society
|December 31, 2008
概括
超快速光谱学揭示了和其氧复合物的分子动力学. 刺激拉曼激发可以实时观察基态化学反应,扩展光谱应用.
科学领域:
- 物理化学 物理化学
- 化学物理 化学物理
- 频谱学是一种光谱学.
背景情况:
- 研究了纯 (CHCl(3) 和氧和 (O(2) -CHCl(3) 电荷转移复合物的超快动力学.
- 之前的研究集中在兴奋状态动态上,对基本状态反应的关注较少.
研究的目的:
- 为了阐明CHCl(3) 和O(2) -CHCl(3) 中的小于5 femtosecond (fs) 的脉冲动态.
- 为了研究由刺激的拉曼过程触发的甲氧化机制.
- 为了证明时间分辨率光谱对基本状态反应的适用性.
主要方法:
- 下-5 fs 时间分辨率光谱学.
- 三光子吸收光谱. 三光子吸收光谱.
- 刺激拉曼光谱法 刺激拉曼光谱法
- 频谱分析. 频谱分析.
主要成果:
- 整洁的CHCl(3) 的动力学是由通过三光子吸收的激发状态波束运动主导的.
- 在O ((2) -CHCl ((3) 中的动力学涉及由刺激的拉曼过程激发的基态波束运动.
- 在O(2) -CHCl(3) 复合体中的氧化通过C-H插入进行,由刺激的拉曼刺激触发.
- 使用光谱分析直接观察了拉曼触发氧化过程的实时动态.
结论:
- 下-5 fs 时间分辨率光谱可以观察激发状态和基本状态化学反应中的过渡状态.
- 刺激拉曼刺激为研究基态反应提供了一条途径,扩大了超快光谱的范围.
- 这种技术适用于广泛的化学反应.
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