Reaction of Hydroxyl Radicals with Two-and Three-Ring Polycyclic Aromatic Hydrocarbons: Determination of Hydrogen Abstraction and Hydrozyl Addition Rates under Combustion and Post-

研究了羟基（OH）自由基与二环和三环多环自动芳烃（PAHs）气相反应的动力学和机理；这个问题在燃烧和大气化学中都是一个基本问题。实验数据收集在延长温度（300-1200oK）和压力（50-750 torr）范围内。为研究半挥发性化合物而改进的脉冲激光光解/激光诱导荧光（PLP/LIF）技术用于动力学和机理测量。实验包括测量压力对观察到的反应速率和动力学同位素效应的影响。实验补充了用从头算量子化学方法对加成和阻碍反应的理论研究。过渡状态理论（TST）用于获得速率约束和分支定量，Rice-Ramperger-Kassel-Marcus （RRKM）理论用于估计中间体的寿命。

This is a study of the kinetics and mechanism of the gas-phase reaction of hydroxyl (OH) radicals with two-and three-ring polycyclic automatic aromatic hydrocarons (PAHs); this matter is of fundamental concern in both combustion and atmospheric chemistry. Experimental data are collected over extended temperature (300-1200oK) and pressure (50-750 torr) ranges. A pulsed laser photolysis/laser-induced fluorescence (PLP/LIF) technique refined for the study of semivolatile compounds is used for the kinetic and mechanistic measurements. Experiments include measurements of the effects of pressure on observed reaction rates and kinetic isotope effects. Experiments are complemented with a theoretical study of addition and obstruction reactions using ab initio quantum chemical methods. Transition-state theory (TST) is used to obtain rate constraints and branching rations, and Rice-Ramperger-Kassel-Marcus (RRKM) theory to estimate lifetimes of intermediates.