On the thermal unimolecular decomposition of the cyclohexoxy radical—an experimental and theoretical study
作者:Oliver Welz、Frank Striebel、Matthias Olzmann
DOI:10.1039/b713286g
日期:——
The kinetics of the thermal unimolecular decomposition of the cyclohexoxy radical (c-C(6)H(11)O) was experimentally studied, and the results were analyzed in terms of statistical rate theory with molecular and transition state data from quantum chemical calculations. Laser flash photolysis of cyclohexylnitrite at 351 nm was used to produce c-C(6)H(11)O radicals, and their concentration was monitored
实验研究了环己氧基自由基(cC(6)H(11)O)的热单分子分解动力学,并根据统计速率理论,结合了来自分子化学和量子化学计算的过渡态数据,对结果进行了分析。环己基亚硝酸盐在351 nm处的激光快速光解用于产生cC(6)H(11)O自由基,并在356.2或365.2 nm激发后通过激光诱导的荧光监测其浓度。实验是在293至341 K的温度和5至55 bar的压力下,以氦气作为浴液进行的。在整个温度范围内,观察到双指数曲线,这表明与预平衡的连续反应。根据我们的量子化学计算,因此,该预平衡对应于通过β-CC键裂变形成6-氧代-1-己基(lC(6)H(11)O),cC(6)H(11)的可逆开环O <-> lC(6)H(11)O(1,-1)。推导出以下与温度相关的速率系数,估计不确定度为+/- 30%:k(1)(T)= 3.80 x 10(13)exp(-50.1 kJ mol(-1)/ RT)s(-