冷HD + D碰撞的立体动力控制2碰撞
Bikramaditya Mandal1, James F E Croft2, Pablo G Jambrina3
1Department of Chemistry and Biochemistry, University of Nevada, Las Vegas, Nevada 89154, USA. naduvala@unlv.nevada.edu.
Physical chemistry chemical physics : PCCP
|June 24, 2024
概括
量子计算显示,D2旋转激发是HD + D2碰撞中的主导过程,与之前的实验解释相反. 这一发现影响了对分子碰撞中的立体动力学控制的理解.
科学领域:
- 物理化学 物理化学
- 量子动力学 量子动力学是什么?
- 分子碰撞分子碰撞
背景情况:
- 使用斯塔克诱导的亚亚巴性拉曼通道 (SARP) 的实验研究探测了HD中的立体动力学控制 (v=1,j=2) +D2碰撞.
- 以前的分析集中在HD的特定旋转过渡,可能会忽视主导的不弹性通道.
研究的目的:
- 在HD+D2碰撞中执行立体动力控制的全维量子计算.
- 为了研究旋转火和激发动力学.
- 将理论预测与实验结果进行比较,特别是SARP实验.
主要方法:
- 使用两个精确的H4潜在能量表面进行了全维量子散射计算.
- 分析的重点是碰撞期间HD和D2分子的旋转过渡.
主要成果:
- 发现与D2旋转激发并发的HD旋转火是两种潜在表面的主导不弹性过渡.
- 这种主导通道的横截面是相同的高清火过渡的弹性散射的四倍.
- 在横截面中观察到共振 (l=3对于正向D2,l=1和l=3对于偏向D2).
结论:
- 在HD+D2碰撞中占主导地位的不弹性过程涉及HD的同时旋转火和D2的激发,这是之前SARP实验分析中没有完全考虑的道.
- 理论计算显示出与弹性和非弹性差异横截面的良好一致性,但与特定过渡的SARP实验的不太令人满意的一致性.
- 这些发现建议重新评估SARP实验对这些分子碰撞中占主导地位的不弹性路径的解释.
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