NH_2自由基与O_3反应机理的从头计算

Ab Initio Study on the Mechanism of Ozone and NH2 Radicals Reaction

采用量子化学从头计算的UMP2(full)方法研究了NH2自由基与臭氧的反应机理,优化了反应物、中间体、过渡态和产物的几何构型,并做了频率分析.结果表明,NH2自由基与臭氧反应有两条反应通道,其中一条反应活化能很小,反应极易发生.化学反应热的计算结果与实验结果吻合较好.

Ab initio UMP2 (full) method has been used to study the mechanism of NH2 + O-3 reaction. The geometry configurations of reactants, productions, intermediates and transition states were optimized at 6-31G* level, and the energy parameters were calculated using Ganssian-3(G3) model. The results show that there are two different pathways for the reaction of NH2 radicals with ozone. One of them has very low activation energy, so it happens easily. Therefore, the results of this theoretical study indicate that NH2 radicals in the atmosphere are able to deplete ozone remarkably.