Jambrina Pablo G, Morita Masato, Croft James F E, Aoiz F Javier, Balakrishnan Naduvalath
Departamento de Química Física, University of Salamanca, Salamanca 37008, Spain.
Department of Chemistry and Biochemistry, University of Nevada, Las Vegas, Nevada 89154, United States.
J Phys Chem Lett. 2022 May 12;13(18):4064-4072. doi: 10.1021/acs.jpclett.2c00587. Epub 2022 May 2.
In recent experiments using the Stark-induced adiabatic Raman passage technique, Zhou et al. ( 2021, 154, 104309; 2021, 374, 960-964) measured the product's angular distribution for the collisions between He and aligned D molecules at cold collision energies. The signatures of the angular distributions were attributed to an [Formula: see text] = 2 resonance that governs scattering at low energies. A first-principles quantum mechanical treatment of this problem is presented here using a highly accurate interaction potential for the He-H system. Our results predict a very intense [Formula: see text] = 1 resonance at low energies, leading to angular distributions that differ from those measured in the experiment. A good agreement with the experiment is achieved only when the [Formula: see text] = 1 resonance is artificially removed, for example, by excluding the lowest energies present in the experimental velocity distribution. Our analysis revealed that neither the position nor the intensity of the [Formula: see text] = 1 resonance significantly changes when the interaction potential is modified within its predicted uncertainties. Energy-resolved measurements may help to resolve the discrepancy.
在最近使用斯塔克诱导绝热拉曼通道技术进行的实验中，周等人（2021年，154卷，104309页；2021年，374卷，960 - 964页）测量了在冷碰撞能量下氦与取向的D分子之间碰撞产物的角分布。角分布的特征归因于一个支配低能散射的J = 2共振。本文使用针对He - H系统的高精度相互作用势对该问题进行了第一性原理量子力学处理。我们的结果预测在低能下有一个非常强的J = 1共振，导致角分布与实验测量的不同。只有当人为去除J = 1共振时，例如通过排除实验速度分布中存在的最低能量，才能与实验取得良好的一致性。我们的分析表明，当相互作用势在其预测的不确定性范围内修改时，J = 1共振的位置和强度都不会显著变化。能量分辨测量可能有助于解决这一差异。
