Abstract: Theoretical studies on the weak π-π interaction-controlled di-nuclear Ag (I) complexAg,(MPTQ)₂²⁺ with folded structure were carried out with DFTmbthod at B3LYP/LanL 2DZlevel.Theelectronic structure of the complex, the characteristic of its bonding, the mechanism of π-π interactions,the atomic net charge populations and the related properties of the complex have been investigated.The re-sults show that there is a weak direct π-π interaction between the two silver atoms in the complex.TheHOMOof the complex is mainly populated on the π-p orbitals of the aromatic rings, the σ-p orbitals of Satoms and s orbitals of C₁₂ atoms, whereas the LUMO is predominantly located on the π^*-p orbitals of thearomatic rings.The electronic spectrum of the ground state of the complex may be predicted to assign tothe n→π^* CTband from the n-p orbitals of Sand s orbitals of C12 to the π^* -p orbitals of the aromaticrings.In addition, the mechanism of π-π interactions among the complex molecules was also further ex-plored.The calculation results can be better used to explain the experimental phenomena and regularities.

Key words: Silver complex, 8-(2-Pyridylmethylthio)quinoline, π-&pi, interaction, DFT method, Electronic structure