| Lanthanide complexes with rich and diverse molecular structures, due to their excellent luminescent properties, can be used in optical communications, defense, biomedical, organic light emitting displays and many other fields. However, as potential functional materials, high nuclear lanthanide complexes are of great potential value, the quantity is relatively limited. Especially, there is still some oscillators such as CH-, NH-or OH-containing solvates around Ln3+ions which can make the luminescence quenching. To overcome these disadvantages, herein, a variety of polynuclear complexes based on series of Salen-type Schiff-base ligands through the introduction of different counter ions have been designed and researched to improve the luminescent properties.In this thesis,36new lanthianide complexes based on the novel Salen-type Schiff ligands (H3L1, H3L2and H2L3) are designed and synthesized. And their structures are characterized by FT-IR, EA,1H-NMR and X-ray crystal diffraction, respectively. Besides, their photophysical properties are also analyzed by UV-Vis absorption spectra, near-infrared and visible excitation and emission spectra.Firstly, the OH-containing Salen-type Schiff base ligand H3L1has been used to get three series of lanthanide complexes, heptanuclear complexes:[Ln6(HL1)(L1)4(μ3-OH)(OAc)2(MeOH)(H2O)·(OAc)(Ln=Nd,1; Ln=Yb,2; Ln=Er,3; Ln=Gd,4; Ln=Eu,5; Ln=Tb,6; Ln=La,7); hetero-binuclear complexes:Zn(HL)(EtOH)(NO3)3Ln](Ln=Nd,8; Ln=Yb,9; Ln=Er,10; Ln=Gd,11; Ln=Eu,12; Ln=Tb,13); hetero-binuclear complexes:[Zn(HL)(OAc)3Ln](Ln=Nd,14; Ln=Yb,15; Ln=Er,16; Ln=Gd,17; Ln=Eu,18; Ln=Tb,19). And their structures are characterized by FI-IR, EA,’H-NMR and X-ray single crystal diffraction, and their photophysical properties are also discussed.Secondly, based on the experience above, H3L2, the novel Salen-type Schiff ligand was synthesized. It was used to prepare a series of lanthanide nonanuclear complexes,[Ln9(HL2)2(L2)3(μ3-OH)4(OAc)10](Ln=Nd,20; Ln=Yb,21; Ln=Er,22; Ln=Gd,23; Ln=Eu,24; Ln=Tb,25; Ln=La,26). And their molecular structures and photophysical properties are also studied.Finally, the Salen-type Schiff base ligand H2L3is used to prepare two series of complexes in different temperatures, hetero-trinuclear:[Zn2(L3)2(MeOH)C1Ln(N3)·C1(Ln=La,27; Ln=Nd,28; Ln=Yb,29; Ln=Er,30; Ln=Gd,31) and hetero-pentanuclear complexes:[Zn2(L3)3C12(μ2-OH)(μ3-OH)2Ln3(N3)2](Ln=La,32; Ln=Nd,33; Ln=Yb,34; Ln=Er,35; Ln=Gd,36). And their molecular structures and photophysical properties are also studied. To the reactions of complexes32to36, where the transmetallation of the partial precursor under higher temperature, leads to the selective exchange of Zn2+center for the Ln3+ion. |
