2,3-二氟苯甲酸铽配合物的合成、晶体结构及荧光性质表征

Synthesis,Crystal Structure and Luminescence Characterization of a Terbium Complex with 2,3-diflurobenzoic Acid

本文采用溶液法合成了双核铽配合物[Tb(2,3-DFBA)3(2,2′-bipy)]2(2,3-DFBA=2,3-二氟苯甲酸根,2,2′-bipy=2,2′-联吡啶),并用X-射线单晶衍射对其晶体结构进行了测定.该配合物属于单斜晶系,P2(1)/n空间群.在配合物中,2个Tb3+离子被4个2,3-二氟苯甲酸根以桥联双齿的方式连接;每个Tb3+离子的配位数为8,分别与4个桥联双齿2,3-二氟苯甲酸根的4个氧原子,1个螯合双齿的2,3-二氟苯甲酸根的2个氧原子以及1个2,2′-联吡啶的2个氮原子配位.该配合物在紫外灯照射下发出强烈的绿光,其荧光光谱在489、545、583和618 nm处出现4条谱线,这是由Tb3+离子的5D4→7Fj(j=6～3)跃迁产生的.

A dinuclear Terbium 2,3-DFBA complex [Tb（2,3-DFBA）3（2,2′-bipy）]2（2,3-DFBA = 2,3-diflurobenzoate,2,2′-bipy = 2,2′-bipyridine） has been obtained by solvent method and further characterized by X-ray diffraction single-crystal structure analysis.The complex crystallizes in Monoclinic system,P2（1） /n space group,with a = 1.224 51（2） nm,b = 1.802 02（3） nm,c = 1.405 36（2） nm,α = 90°,β = 112.295 0（10）°,γ = 90°.In the complex,two Tb3 ＋ ions are linked by four 2,3-DFBA ligands in bridging-bidentate coordination modes.Each Tb^3 ＋ ion is eight-coordinated,with four oxygen atoms from four bridging 2,3-DFBA ligands,two oxygen atoms from one chelating-bidentate 2,3-DFBA ligand and two nitrogen atoms from one 2,2′-bipy molecule.The complex exhibits strong green fluorescence under ultraviolet light.The luminescence spectrum of the complex was measured at the room temperature,and the four emission bands are at 489,545,583 and 618nm,corresponding to 5D4→7F6,5D4→7F5,5D4→7F4 and 5D4→7F3 transitions of the Tb3 ＋ ion.