摘要
对甲酸甲酯正离子自由基单分子分解的三个反应通道:用ab initio SCF MO方法,在STO-3G基组上进行了量子化学的计算研究。给出了反应(1)和反应(2)在C_5对称性下反应途径的态相关图。并在相关基础上探讨了基态和低激发态的反应过程。对反应(3)的研究是在C_1对称性下进行的。分别优化得到了反应(1)和反应(3)的一个过渡态和一个中间体。分析了每个分解反应在反应过程中的物理化学性质的变化。对反应(1)和反应(3)用MCSCF/STO-3G方法校准的活化位垒分别为193.24kJ·mol^(-1)和346.48kJ·mol^(-1)。
Three reaction pathways of the unimolecular dissociation of methylformate radical cationCH_3OCHO^+→CH_3OH^++CO (1)CH_3OCHO^+→CH_3O+HCO^+ (2)CH_3OCHO^+ CH_2OH^++HCO (3) were studied by ab initio SCF MO method at the UHF/STO-3G level. The state correlation diagrams in Cs symmetry for reaction (1) and reaction (2) were examinated and some reaction pathways for ground and low-lying excited states were carried out based on the result of correlation diagrams. We investigated tne path of reaction (3) path in Cl symmetry. The transition states and the intermidiates for reaction (1) and reaction (3) were optimazed. Furthermore, the physical chemical variations along each reaction pathway were discussed. The activation barriers were corrected by using MCSCF method (193.24kJ·mol^(-1)and 346.48 kJ· mol^(-1) respectively for reaction (1) and reaction (3)).
基金
国家教委博士点基金
