Spectroscopy Predissociation Dynamics and Scattering of Van der Waals Systems

在这项由化学学部实验物理化学项目资助的提案中，乔治亚大学的Henning Meyer将继续研究范德华体系的光谱学、预解离和散射。利用红外光谱和分子束散射技术研究了电子基态和预离解动力学。范德华体系涉及不同的内部角动量来源，电子（NO）和内部旋转（乙醛），将与水、CO、氮、甲烷和HF等分子络合。本文将研究内部角动量对配合物束缚能级结构的影响，以及配合物在双分子碰撞中的能量传递效率。共振增强多光子电离（REMPI）和离子飞行时间分析将用于分析碎片。将对数据进行分析，以确定内部角动量对分子间动力学的影响，例如，关于旋转-电子耦合和大振幅振动中的非绝热效应。实验研究将辅以严格的理论处理，要么基于第一原理，要么在合理的近似框架内。本研究收集的数据将为分子间能量传递和基本反应动力学提供新的见解。特别是对乙醛（一种由对流层碳氢化合物氧化产生的重要空气污染物）的研究，增加了对对流层臭氧形成的认识。因此，这个基础项目对于理解更实际的环境问题（如全球变化）非常重要。

In this proposal funded by the Experimental Physical Chemistry Program of the Chemistry Division, Henning Meyer of the University of Georgia will pursue a program of research on the spectroscopy, predissociation, and scattering of van der Waals systems. IR and molecular beam scattering are used to study the electronic ground state and predissociation dynamics. Van der Waals systems involving different sources of internal angular momentum, electronic (NO) and internal rotational (acetaldehyde), will be complexed with molecules such as water, CO, nitrogen, methane, and HF. The influence of the internal angular momentum on the bound level structure of the complexes will be studied, as will the energy transfer efficiency of the complexes in bimolecular collisions. Resonance enhanced multiphoton ionization (REMPI) and ion time of flight analysis will be used to analyze fragmentation. The data will be analyzed with a view to establishing the effects of the internal angular momentum on the intermolecular dynamics, for example, with respect to non-adiabatic effects in rotational-electronic coupling and to large amplitude vibrations. The experimental studies will be complemented by a rigorous theoretical treatment, either based on first principles or within the framework of reasonable approximations.The data gathered in this study will provide new insights relevant to intermolecular energy transfer and elementary reaction dynamics. In particular, the studies on acetaldehyde, an important air pollutant resulting from the oxidation of tropospheric hydrocarbons, adds to the understanding of the formation of tropospheric ozone. This fundamental project thus is important for understanding more practical environmental issues such as global change.