HCF(~1A')+SO_2反应的动力学研究  

Kinetic Study on the Reaction of HCF(~1A')+SO_2

作　　者：杨学良[1] 徐刚[1] 陈旸[1] 陈从香[1] 

机构地区：[1]中国科学院选键化学开放实验室中国科学技术大学化学物理系,合肥230026

出　　处：《化学学报》2006年第1期47-53,共7页Acta Chimica Sinica

基　　金：国家自然科学基金(Nos.10032050;20373065;20328305);国家重点基础专项研究基金(No.G1999075304)资助项目.

摘　　要：用激光光解-激光诱导荧光方法研究了室温下(T=293K)HCF(X%A′)自由基与SO2分子的反应动力学.实验中1HCF(X%A′)自由基是由213nm激光光解HCFBr2产生的,用激光诱导荧光(LIF)检测HCF(X%A′)自由基的相对浓度随着11反应时间的变化,得到此反应的二级反应速率常数为:k=(1.81±0.15)×10-12cm3?molecule-1?s-1,体系总压为1862Pa.高精度理论计算表明,HCF(X%A′)和SO2分子反应的机理是典型的加成-消除反应.我们运用RRKM-TST理论计算了1此二级反应速率常数的温度效应和压力效应,计算结果和室温下测定的二级反应速率常数符合得较好.HCF（~X^1A′） radicals were produced by laser photolysis of HCFBr2 at 213 nm, and electronically excited from the ground state to ~A^1A′（030） at 492.70 nm with a dye laser pumped by a Nd ： YAG laser. The reaction rate constant of HCF（~X^1A′） with SO2 at room temperature （T=293 K） was determined to be k= （1.81±0.15）× 10^-12 cm^3·molecule^- 1·s^-1, when the total pressure was 1862 Pa. Based on the high level ab initio calculations, the mechanism of this reaction was proved to be a typical addition-elimination reaction. The temperature and pressure dependences of the total reaction rate constant were calculated by applying RRKM-TST model. The calculations could provide a well consistent description for our experimental work.

关 键 词：HCF(~X^1A′)自由基 激光光解-激光诱导荧光 反应速率常数 压力效应 温度效应 

分 类 号：O643.1[理学—物理化学] TS221[理学—化学]