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Updated: Sep 15, 2025

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关于D2{1,15) 和N2之间的碰撞诱导的旋转能量转移的实验研究
Jiaxin Lin1,2, Maofu Yu1,2, Jing Liu1,2
1Xinjiang Key Laboratory of Solid State Physics and Devices, Xinjiang University, Urumqi 830017, China.
The Journal of chemical physics
|July 15, 2025
概括
研究了 (D2) 分子的碰撞旋转放松. 发现- (N2) 碰撞显著加速放松,温度影响能量传递路径.
科学领域:
- 分子物理学 分子物理学
- 化学动力学 化学动力学
- 频谱学是一种光谱学.
背景情况:
- 了解碰撞能量转移对于等离子体物理学和燃烧化学至关重要.
- (D2) 和 (N2) 是各种化学环境中重要的物种.
- 旋转放松动力学会影响反应速率和热力学特性.
研究的目的:
- 实验性地研究激发分子 (D2) 与D2和N2.2发生碰撞时的碰撞旋转放松.
- 为了确定各州的旋转放松率系数.
- 阐明N2度和温度对放松通路的影响.
主要方法:
- 使用激发的拉曼送,制备激发的D2{\displaystyle D2}{\displaystyle D2}{\displaystyle D}{\displaystyle D}{\displaystyle D}{\displaystyle D}{\displaystyle D}{\displaystyle D}{\displaystyle D}{\displaystyle D}{\displaystyle D}{\displaystyle D}{\displaystyle D}{\displaystyle D}{\displaystyle D}{\displaystyle D}{\displaystyle D}{\displaystyle D}{\displaystyle D}}{\displaystyle D}{\displaystyle D}{\displaystyle D}{\displaystyle D}{\displaystyle D}{\displaystyle D}{\displaystyle D}{\displaystyle D}}
- 时间解析的连贯反斯托克斯拉曼散射 (CARS) 光谱测量有效寿命.
- 斯特恩-沃尔默方程用于动力分析的应用.
主要成果:
- 对D2-D2碰撞的自我放松率系数确定为 (2.3 ± 0.1) × 10-14 cm3 s-1.
- 量化了D2-D2和D2-N2碰撞的旋转放松率系数.
- 接近共振的旋转振动 (R-V) 与N2的碰撞加速D2的放松.
- 多量子放松 (J = 15 → 11) 主导着D2-D2相互作用,而单量子放松 (J = 15 → 13) 随着N2的增加而变得突出.
- 温度效应显示D2-D2在更高温度下增强的多量子放松,D2-N2.2增加的单量子放松.
结论:
- 与N2的碰撞相互作用显著改变了激发D2.2的旋转放松路径.
- 多量子和单量子放松之间的平衡取决于碰撞伙伴和温度.
- 这些发现为模拟涉及同位素和的反应系统提供了关键数据.
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