在强烈的秒激光场中,对齐的O2的离离离离电离和离离后对齐
Shinichi Fukahori1,2, Ayumi Kubo1, Hirokazu Hasegawa1,2
1Department of Integrated Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan. chs36@mail.ecc.u-tokyo.ac.jp.
Physical chemistry chemical physics : PCCP
|October 9, 2024
概括
在激烈的激光场中研究氧分子 (O2) 解离的过程揭示了两个不同的电离路径. 这些路径取决于分子对齐,影响O+离子动能和电子发射轨道.
科学领域:
- 物理化学 物理化学
- 原子和分子物理 原子和分子物理
- 激光物理 激光物理
背景情况:
- 了解激烈激光场中的分子动力学对于控制化学反应至关重要.
- 五秒激光脉冲可以探测超快的过程,如分子对齐和电离.
研究的目的:
- 为了研究氧分子 (O2) 的解离性电离,使用强烈的秒激光场.
- 分析O+离子的动能分布作为探头延迟时间的函数.
- 阐明分子对齐和电子发射轨道在离离电离化的作用.
主要方法:
- 实验设置涉及强烈的秒激光场 (782 nm,120 fs,4 × 10^14 W cm^-2).
- 使用飞行时间质谱仪测量O+动能分布的时间分辨率.
- 探头技术用于控制分子对齐和研究电离动力学.
- 经典轨迹蒙特卡罗 (CTMC) 模拟O2+解离.
主要成果:
- 在O+动能分布中观察到两种不同的,异相的旋转复苏模式.
- 当O2与激光场平行对齐时,增强解离性电离,表明来自3σg轨道的电离.
- 当O2与激光场垂直对齐时,增强分离性电离,表明从1πu轨道的电离.
- 由探测器脉冲影响的O2+的离子化后对齐的证据.
结论:
- 在强烈的激光场中,O2的离离离电离是由来自不同轨道 (3σg和1πu) 的独特路径控制的.
- 分子对齐在确定主导的电离通道方面发挥着关键作用.
- 离子化后的动态,包括分子对齐,显著影响观察到的O+离子产量和能量分布.
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