Molecular Beam Studies of Spin-Orbit Effects and Anisotropy in Penning Ionization

在化学学部物理化学项目中，匹兹堡大学的Peter Siska教授将研究稀有气体原子与其他原子或双原子分子的交叉分子束反应。具体来说，Penning和缔合电离动力学将使用Penning电离电子能谱（PIES）进行研究。还包括亚稳惰性气体的原子和分子散射的理论研究，在特定状态的水平。当电子激发的原子A*遇到分子BC时，原子可能通过多种途径失去能量。在某些情况下，原子能量的损失导致中间分子络合物的一个电子被射出，留下一个带正电的离子，可能是ABC+、BC+或AB+。这种过程被称为“潘宁电离”，并已被用于阐明大型有机分子的电子或分子结构，金属表面上的吸附物，甚至液体表面。这些应用之所以成为可能，是因为潘宁电离对单个分子轨道（即分子的电子云）的空间范围和形状很敏感。在这个项目中，我们将研究涉及潘宁电离的各种反应，以回答有关这一过程工作机理的一些基本问题。

In this project in the Physical Chemistry Program of the Chemistry Division, Prof. Peter Siska of the University of Pittsburgh will study crossed molecular beam reactions involving noble gas atoms with other atoms or diatomic molecules. Specifically, Penning and associative ionization dynamics will be investigated using Penning ionization electron spectroscopy (PIES). Also included are theoretical studies of the scattering of metastable noble gases by atoms and molecules on a state-specific level. %%% When an electronically excited atom A* meets a molecule BC, the atom may lose its energy by a variety of pathways. In some circumstances the loss of the atom's energy results in the ejection of an electron from the intermediate molecular complex, leaving a positively charged ion, which may be ABC+, BC+, or AB+. Such processes are known by the name "Penning ionization" and have been used to elucidate the electronic or molecular structure of large organic molecules, adsorbates on metal surfaces, and even liquid surfaces. These applications are possible because Penning ionization is sensitive to the spatial extent and shape of individual molecular orbitals, that is, the molecule's electron clouds. In this project various reactions involving Penning ionization will be examined in order to answer some basic questions regarding the mechanism by which this process works.