双核稀土配合物的合成表征及其光学性能(英文)

Synthesis,Characterization and Luminescence Properties of Dinuclear Lanthanide Complexes

合成了一种新的双β二酮配体1,4-二苯甲酰乙酰苯（TDAP）,并成功合成了它的两个双核稀土配合物Eu2（TDAP）3·（H2O）2和Tb2（TDAP）3·（H2O）6。通过元素分析、红外光谱、紫外可见光谱和荧光光谱对配合物进行了表征与性能研究。荧光分析表明,在紫外灯下配体本身就发出蓝紫色荧光,通过对配体TDAP的磷光光谱分析计算得到了配体的平均三重态能级。配合物Eu2（TDAP）3·（H2O）2的发射光谱分析表明,配体自身的发射几乎完全被淬灭,能量成功传递给了中心离子,因此配合物发出了明显的特征峰,主发射峰为Eu^3 ＋的5D0-7F2发射。由荧光分析知,配合物Eu2（TDAP）3·（H2O）2的激发光谱与配体发射光谱的重叠,这验证了配体TDAP对于Eu^3 ＋能量传递的有效性。此外,还详细分析了两种配合物的能量传递过程及发光机理,配合物Tb2（TDAP）3·（H2O）6几乎不发光,这是因为配体的三重态能级与Tb3＋的最低激发态能级不匹配。合成的配合物Eu2（TDAP）3·（H2O）2有很强荧光,是一种有效的红色发光材料。

Two new complexes of Eu（Ⅲ） and Tb（Ⅲ） chelated with bis（β-diketone） terephthaloyl-diacetophenone （TDAP） were successfully synthesized.The samples were characterized by the element analysis,infrared spectra,UV-Vis spectra,1H NMR and fluorescence spectra.The results indicated that their compositions are Eu2（TDAP） 3· （H2O） 2 and Tb2（TDAP） 3·（H2O） 6,respectively.Photoluminescence measurement indicated that TDAP is a good indigo emitter under UV radiation.The average triplet state energy of the ligand was obtained by analyzing the phosphorescence spectrum of TDAP.The Eu（Ⅲ） complexes display characteristic metal-centered luminescence,while the ligand emissions are completely quenched.The results indicated that the efficient ligand-to-metal energy transfer （antenna effect） occurs.The characteristic red emission appears due to the 5↑D0→7↑Fj transitions of the 4f electrons of the central Eu^3 ＋ ions.Tb2（TDAP） 3·（H2O） 6 has poor fluorescence property,this is because the triplet state energy of the ligand does not match with the lowest excited state energy of Tb^3 ＋ ions.The possible energy transfer mechanism was investigated.