Ab initio and DFT study on [Si(O_2Ph)_n]~(m±) (n = 1-3, m=0,±2)

摘要

Calculations of the stable structures and binding energies of [Si(O_2Ph)_n]~(m±) (n = 1-3,m = 0,±2) have been carried out using ab initio HF and density functional theory B3LYP methods with different basis sets. The basis set superposition errors of the binding energies of the complexes were corrected by the counterpoise method. The composition characteristics of some frontier molecular orbitals in the complexes were discussed. All the complexes can stably exist in potential energy surfaces. The binding energies decrease accordingly with the increase in coordination number of silicon. In the tris(o-phenyl-enedioxy) silicon anion [Si(O_2Ph)_3]~(2-), the d orbitals of silicon contribute little to the stability of the complex, which is different from the transition metal hexacoordinated complexes with a d~2sp~3 hybridization of the central metal. The contribution to the stability of [Si(O_2Ph)_3]~(2-) is from the formation of Si-O single bond, as well as the interaction of molecular orbitals among three PhO_2~(2-) fragments.