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应用分子模拟半经验量子力学Mopac 6．0-AM1近似计算方法分析了分子筛催化甲苯歧化反应的S_E~1反应历程,确定了反应历程中的反应态、过渡态和产物态,得到了反应活化能和反应热等相关信息,对内禀反应坐标的计算进一步验证了反应过程中的能量变化。计算结果表明,分子筛催化的甲苯歧化反应沿S_E~1反应历程可通过两步基元反应完成；质子由分子筛向甲苯分子转移的过程为反应的快速步骤,其活化能达到428．54 kJ·mol~(-1),需要在高温下进行；甲苯歧化总反应的热效应很小,与实验数据相吻合。
The reaction process of toluene disproportionation with molecular sieve was analyzed by Mopac 6.0-AM1 molecular simulation method. The reaction states, transition states and product states of the reaction were determined. The reaction activation energy And reaction heat and other related information, the calculation of intrinsic reaction coordinates further verify the energy changes in the reaction process. The results show that the reaction of toluene disproportionation catalyzed by molecular sieve can be completed by the two-step elementary reaction along the reaction process of S_E ~ 1. The transfer of proton from molecular sieve to toluene molecules is a fast reaction, and the activation energy reaches 428.54 kJ · mol ~ (-1), which needs to be carried out at high temperature. The thermal effect of the total reaction of toluene disproportionation is very small, which is consistent with the experimental data.