含2，2＇-联嘧啶桥Ir^III-Ln^III（Ln=Nd，Yb，Er）双金属配合物的合成和光物理性质

选择具有（N^N）（N^N）位点的四齿配体2,2’-联嘧啶fbpm）作为桥联配体，利用铱配合物Ir（dfppy）2（bpm）Cl作为配体与稀土配合物Ln（TTA）3·2H2O配位，得到了Ir^III-Ln^III（Ln=Nd，Yb，Er）双金属配合物Ir（dfppy）2（bpm）Ln（TTA）3]Cl．通过荧光滴定的方法，测定了该铱配合物与稀土离子之间的络合稳定常数．通过对铱配合物及Ir^III-Ln^III（Ln=Nd，Yb，Er）双金属配合物在可见区光谱的测定，可以观察到明显的铱配合物发光的猝灭，说明从铱中心到稀土中心发生了能量传递．同时，利用可见光选择性激发铱配合物可以获得在稀土Nd^III，Yb^III，E^III离子红外区的发光．说明了铱配合物Ir（dfppy）2（bpm）Cl作为配体可以较好地敏化稀土离子的红外发光．

Synthesis and photophysical properties of Ir^III-Ln^III （Ln = Nd,Yb, Er） bimetallic complexes using bipyrimidine as bridging ligand

Bipyrimidine was chosen as （N^N）（N^N） bridging ligand for connecting metal centers. Ir^III-Ln^III （Ln = Nd, Yb, Er） bimetallic complexes Ir（dfppy）2（μ-bpm）Ln（TTA）3]Cl were synthesized by using Ir（dfppy）2（bpm）Cl as ligand coordinating to lanthanide complexes Ln（TTA）3.2H2O. The stability constants between Ir（dfppy）2（bpm）Cl and lanthanide ions were measured by fluorescence titration. The obvious quenching of visible emission from Ir^III complex in the Ir^III-Ln^III （Ln = Nd, Yb, Er） bimetallic complexes indicated that energy transfer occurred from Ir^III center to lanthanides. NIR emissions from Nd^III, Yb^III, Er^III were obtained under the excitation of visible light by selective excitation of the Ir^III-based chromophore. It was proved that Ir（dfppy）2（bpm）Cl as ligand could efficiently sensitize NIR emission from Nd^III, Yb^III, Er^III.