新型羧酸类铽(Ⅲ)三元配合物的合成与荧光性质的研究

摘要

以2-苯胺羰基苯甲酸(HAB),2-二苯胺羰基苯甲酸(HDPAB)为第一配体,咪唑并[5,6-f]邻菲罗啉(IP)为第二配体,合成出两种新型稀土铽三元配合物.通过元素分析确定了配合物的组成为T-b(HAB)3 IP和Tb(HDPAB)3 IP.红外光谱的分析表明HAB和HDPAB中的氧原子以及IP中的氮原子与稀土离子进行配位.紫外光谱的分析表明两种配合物中的能量传递主要来自第一配体,且配体HAB的能量传递效率大于HDPAB.通过荧光光谱研究了配合物的发光性质,结果显示两种配合物均表现出稀土离子的特征发射,当第一配体的结构发生变化时,二者的发光强度发生了明显的变化,这是由于HDPAB中的氮原子上增加一个苯环后,改变了体系中电子云的分布情况,导致π-π*跃迁吸收的能量不能有效的通过Antenna效应传递给稀土中心离子,使得配合物Tb(HDPAB)3 IP的发光强度降低.%In the present paper, imidazo[5,6-f] phenthroline(IP), 2-aniline carbonyl benzoic acid (HAB) and 2-diphenylamine carbonyl benzoic acid(HDPAB) were synthesized at room temperature. Under the same condition, with HAB and HDPAB as the first ligand and IP as the secondary ligand, two novel ternary organic terbium complexes were prepared in ethanol solution. Elemental analysis demonstrated that the chemical formula of the two ternary complexes were Tb(HAB)3 IP and Tb(HDPAB)3 IP.The spectroscopic properties of the ligands and complexes were also discussed. IR spectra indicated that rare earth Tb3+ ion was coordinated with oxygen atoms of the first ligand HAB and HDPAB and two nitrogen atoms of the secondary ligand IP. The UV spectra showed that the main absorption was from the first ligand in the ternary complexes, the secondary ligand was bonded to rare earth Tb3+ ion and the energy transfer efficiency of HAB was higher than that of HDPAB. The excitation and emission spectra of the two terbium complexes were measured and investigated, especially by comparing their fluorescence intensities.Fluorescence spectra demonstrated that the two kinds of ternary organic terbium complexes could emit characteristic fluorescence of rare earth Tb3+ ion. But the fluorescence intensity of Tb(HAB)3IP was obviously higher than that of Tb(HDPAB)3 IP. Compared with two first ligands HDPAB and HAB, the fluorescence intensities of the two ternary organic terbium complexes were found to be influenced by the molecule structure, and the benzene ring which was coordinated with nitrogen atom increased in HDPAB. In the system of ternary complexes, due to the different coordinated number of benzene ring, the mobility of electron and the distribution of electron cloud were changed. The variation affected the transition of the π electrons, which can take in theenergy in ternary complexes. So, the energy transfer efficiency from the first ligand to rare earth Tb3+ ion decreased and Antenna effect achieved inefficiency in Tb(HDPAB)3 IP.