过渡金属配合物CuF^(+)活化甲烷的理论研究

Theoretical study on methane activation by transition metal complex CuF^(+)

使用密度泛函理论(DFT),在B3LYP/RECP+6-311+G^(**)水平下构建了CuF^(+)与甲烷反应的反应势能面,分析了C-H键活化过程中几何结构优化情况,研究了CuF^(+)活化甲烷过程中的详细细节,为活化甲烷及C-H键的研究提供理论依据.利用内禀反应坐标(IRC)对其进行验证,并进行NBO分析.结果表明,反应有利途径为二重态下解离出HF的通道,该通道上各驻点能量均低于基态反应物,且为放热反应,是动力学和热力学均有利的反应.反应机理为氢原子转移过程.

The potential energy surface of the reaction of CuF^(+)with methane has been calculated using the density functional theory(DFT)method based on the B3LYP/RECP+6-311+G^(**)level.The geometric structures were analyzed,and the details of the activation of methane by CuF^(+)were studied,which provided a theoretical basis for the methane activation and C—H bonds.Intrinsic reaction coordinate(IRC)calculations were performed to confirm the optimized transition state.The natural bond orbital(NBO)analysis had been made to give further insight into their bonding properties.The results showed that the favorable pathway is the channel for HF dissociation in the doublet state.The energy of each immediate state on the channel is lower than that of the ground state,and it is an exothermic reaction,which is favorable in terms of kinetics and thermodynamics.The process is hydride transfer mechanism.