自由基簇射降解甲苯和二甲苯的量子化学研究

Quantum chemical study in removing toluene and dimethyl-benzene by using a corona radical shower system

采用密度泛函法(DFT),同时考虑典型的异构,对甲苯、二甲苯中的C—C,C—H键解离能进行计算,计算结果与实验值较好地吻合。分析对比了各解离能的大小,发现甲基上的C—H键解离能最小,苯环侧链上的C—C键解离能稍大,其他C—H键解离能最大。从而指出了甲苯二甲基取代苯中键解离能大小的一般规律,预测了自由基解离甲、苯二甲苯的通道及其解离所需要的能量。结合蒙特卡罗模拟出的气隙空间电子平均能量分布,指出了断裂特定共价键所需输入的电压值。

The bond dissociation energies （BDEs） of methyl - Benzene, 1,2 -dimethyl-Benzene, 1,3-dimethyl-Benzene and 1,4-dimethyl-Benzene were calculated with B3LYP density functional theory （DFT） considering the typical isomerous configurations as well. The results accord with the experimental ones well. The calculated values of BDEs were analysed and contrasted with one another. It was discovered that BDE of C--H of CH3 radical was the least, and the one of C - C linking side chain to C of phenyl was lower than that of other BDEs of C--H. The general dissociation principle of the organic compounds referred above was indicated. Accordingly the dissociation channels of them using a corona radical shower system was predicted, so was the energy input in the corona radical shower system. In terms of average energy distribution of air gap with Monte Carlo simulation, the corresponding voltage to dissociate the given covalent bond is indicated.