采用基于周期性边界条件的密度泛函理论研究了HSAPO-34分子筛上甲醇通过氧鎓叶立德机理直接耦合生成乙烯的可能性.结果表明,二甲醚和三甲基氧鎓离子在HSAPO-34分子筛上的生成能垒分别为1.68和0.93eV,中间体氧鎓叶立德不能稳定存在,同时表明C–C键通过协同反应形成的能垒均超过3.0eV.因此,甲醇制烯烃催化过程不可能遵循氧鎓叶立德机理. The possibility of direct coupling of methanol on HSAPO-34 molecular sieve through oxonium ylide mechanism to ethylene was studied by means of density functional theory based on periodic boundary conditions. The results showed that dimethyl ether and trimethyl- On the other hand, the formation energy barriers of 1.68 and 0.93eV, respectively, the intermediate oxonium ylide can not exist stably, at the same time, the energy barrier of C-C bond formed by the synergistic reaction is more than 3.0eV. Therefore, Onium ylide mechanism.