图像旋转能量转移:CO + N2和CO + CO无弹性散射中的比较立体动力学
Zhong-Fa Sun1, Roy J A Scheidsbach2, Marc C van Hemert3
1Anhui Province Key Laboratory of Optoelectric Materials Science and Technology, Department of Physics, Anhui Normal University, Wuhu, Anhui 241000, China. zfsun@ahnu.edu.cn.
Physical chemistry chemical physics : PCCP
|June 28, 2023
概括
在13CO + N2碰撞中研究了状态到状态的旋转能量转移. 实验和理论之间的良好一致性证实了CO-N2潜在能量表面,揭示了相似的对齐动态,但由于PES异构性而分散的差异.
科学领域:
- 化学物理 化学物理
- 分子碰撞分子碰撞
- 频谱学是一种光谱学.
背景情况:
- 从一个州到另一个州的旋转能量转移对于理解分子碰撞至关重要.
- 之前的研究在类似的条件下探索了CO + CO碰撞.
研究的目的:
- 调查13CO + N2碰撞中的旋转能量转移.
- 将实验结果与使用新的潜在能量表面 (PES) 的理论预测进行比较.
- 用CO + CO散射分析差异和相似之处.
主要方法:
- 交叉分子束方法.
- 真空紫外线 (VUV) 共振增强的多光子电离与速度图形离子成像.
- 在新的13CO-N2 PES上进行准经典轨迹 (QCT) 计算.
主要成果:
- 实验差分截面 (DCS) 和QCT预测之间的良好一致性.
- 对13CO-N2 PES精度的实验和理论确认.
- 类似的旋转角动量调整时刻用于CO + N2和CO + CO,表明硬外动态.
- DCS的差异,包括向后移动的彩虹最大值和13CO + N2的不那么明显的次要最大值,这表明13CO-N2 PES.
- 在13CO + N2碰撞中缺少具有高旋转激发的前向散射元件.
结论:
- 新的CO-N PES准确地描述了观察到的状态到状态的旋转能量转移.
- 碰撞诱导的对齐动态在CO + N2和CO + CO系统中都受到硬外的控制.
- PES的异构差异解释了散射模式的变化,例如彩虹峰的位置和缺乏特定的前向散射组件.
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