Vibrationally and Rotationally State-Resolved Differential Cross Sections for Reactive Scattering

俄克拉荷马大学的Mark Keil和Gregory A.Parker在实验物理化学计划的支持下，继续研究各种简单反应的状态-状态反应动力学：(I)氟原子与氢二聚体形成氟化氢；(Ii)氟原子与氯化氢形成氟化氢和氯原子；(Iii)氯原子与溴化氢形成氯化氢和溴原子。感兴趣的反应发生在两个交叉的分子束的交叉处。然后使用高分辨率的化学激光器和测辐射热计探测器来解析散射产物的VIB旋转态和角分布。PI将探索不同的初始转动能和动能，以及同位素取代对振动和转动状态分辨的微分截面的影响。我们将直接与从头算理论动力学计算进行比较，这些计算使用的是由共同PI开发的量子散射程序。这些研究的主要目的是加深我们对化学反应动力学在详细的状态到状态水平的理解。使用近似技术来简化日益复杂的化学反应问题，目前正在取得巨大的理论进展。在这种量子计算中使用的近似的有效性通常基于这里研究的三原子A+BC系统的经验：对A+BC系统的详细研究为理解更大的系统提供了基础。详细的化学反应动力学领域正在非常广泛地帮助阐明化学反应，与化学的所有分支都有明显的相关性。

Mark Keil and Gregory A. Parker of the University of Oklahoma are supported by the Experimental Physical Chemistry Program to continue their investigations on state-to-state reaction dynamics for various simple reactions: (i) fluorine atoms plus hydrogen dimer to form hydrogen fluoride; (ii) fluorine atoms and hydrogen chloride to form hydrogen fluoride and chlorine atoms; (iii) chlorine atoms and hydrogen bromide to form hydrogen chloride and bromine atoms. The reaction of interest takes place at the intersection of two crossed molecular beams. A high-resolution chemical laser in conjunction with a bolometer detector is then used to resolve the scattered product vib-rotational state and angular distribution. The PIs will explore the effects of varying initial rotational and kinetic energies, and isotopic substitutions, upon the vibrationally and rotationally state-resolved differential cross sections. Direct comparisons will be made with ab initio theoretical dynamical calculations using quantum scattering codes developed by the co-PI. The principal goal of these studies is to deepen our understanding of chemical reaction dynamics at the detailed state-to-state level. Tremendous theoretical progress is currently being made using approximation techniques for simplifying increasingly complex chemical reactivity problems. The validity of approximations used in such quantum calculations is often based upon experience with tri-atomic A+BC systems of the sort studied here: detailed investigations of A+BC systems have provided the foundation upon which larger systems can be understood. The field of detailed chemical reaction dynamics is helping elucidate chemical reactivity very broadly, with obvious relevance to all branches of chemistry.