Structure of Hydrogen-Bond and the Topological Properties of Electronic Density

The Ab initio （6-31G**） calculations on （H₂O）₂, （HF）₂, （NH₃）₂, H₂OHF, H₃NHF,H₃NH₂O, H₂OH₃N hydrogen-bond system were carried out. According to the calculated results, the relationships of the topological property and characteristic with the strenth of hydrogen-bond, the Laplacian -▽~²ρ（r_c） with the extensional direction of lone-pair electron and the forming direction of hydrogen-bond are discussed. The changes of chemical bonds in the forming process of hydrogen-bond are also discussed.