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合成了4种Eu(Ⅲ)-β-二酮-氨基多羧酸三元配合物,经元素分析和化学分析测定其组成分别为K_2[Eu(CYDTA)BA)·2H_2O(Ⅰ)、K[Eu(NTA)BA]·2H_2O(Ⅱ)、K_2[Eu(IDA)_2BA](Ⅲ)和K_2[Eu(EDTA)BA](Ⅳ),用红外光谱、差热分析进行了表征.测定了配合物Ⅰ～Ⅳ在室温(298K)和液氮湿度(77K)下的荧光发射光谱,应用群论方法和Judd-Ofelt理论对低温精细光谱作了归属,根据配合物发射峰~5D_0→~7F_J(J=0.1,2和4)的Stark劈裂及强制电偶极f-f跃迁选律推断出配合物中心离子Eu(Ⅲ)的点对称性分别为:Ⅰ,C_(2v);Ⅱ,D_(3h);Ⅲ,C_4;Ⅳ,S_4.从荧光发射强度计算出表征Eu(Ⅲ)-配体共价程度的荧光发射相对强度参数η值(η=1(~5D_0→~7F_2)/I(~5D_0→~7F_1)依次为:1,5.8;Ⅱ,9.4;Ⅲ,11.2;Ⅳ,16.4.研究了配合物Ⅰ～Ⅳ的紫外-可見吸收光谱,测定了其在丙酮/水(1:1)溶液中的超灵敏跃迁振子强度P(~7F_0→~5D_2)分别为:1,0.32×10~(-6);Ⅱ,0.40×10~(-6);Ⅲ,0.52×10~(-6),Ⅳ,0.73×10~(-6).发现Eu(夏)配合物的吸收光谱超灵敏跃迁振子强度P(~F_0→~5D_2)与发射光谱的荧光相对参数η(I~5D_0→~7F_2)/I(~5D_0→~7F_1))之间存在线性关系:P=0.04η+0.066,由此得出Eu(Ⅲ)与配体间键的共价程度是影响超灵敏跃迁强度的主要因素,而与Eu(Ⅲ)点对称性无直接联系.
Four kinds of Eu (Ⅲ) -β-dione-aminopolycarboxylic acid ternary complexes were synthesized and their compositions were determined as K 2 [Eu (CYDTA) BA) · 2H 2 O Eu (NTA) BA] 2H2O, K_2 [Eu (IDA) 2BA] (Ⅲ) and K_2 [Eu (EDTA) BA] (Ⅳ) were characterized by FTIR, The fluorescence emission spectra of the compounds Ⅰ ~ Ⅳ at room temperature (298K) and liquid nitrogen humidity (77K) were assigned to the low-temperature fine spectrum by the method of group theory and Judd-Ofelt theory. According to the emission peak of complexes ~ 5D_0 → ~ 7F_J J = 0.1, 2, and 4) and the forced electric dipole ff transition law, the point symmetry of the Eu (Ⅲ) ions in the complex was deduced as follows: Ⅰ, C 2v; ); Ⅲ, C_4; Ⅳ, S_4. From the fluorescence emission intensity, the relative intensity parameter η (η = 1 (~ 5D_0 → ~ 7F_2) / I 5D_0 → ~ 7F_1) were as follows: 1,5.8; Ⅱ, 9.4; Ⅲ, 11.2; Ⅳ, 16.4. The UV-Vis absorption spectra of complexes Ⅰ ~ Ⅳ were studied. The intensity of superconducting transition oscillator P (~ 7F_0 → ~ 5D_2) in the solution were: 1, 0.32 × 10 -6, Ⅱ, 0.40 × 10 -6, Ⅲ, 0.52 × 10 -6 ), Ⅳ, 0.73 × 10 ~ (-6) .It is found that the fluorescence relative parameters η (I ~ 5D_0 → ~ 7F_2) / I (~ 5D_0 → ~ 7F_1)): P = 0.04η + 0.066, which indicates that the degree of covalent bonding between Eu (Ⅲ) and the ligand is the major factor influencing the intensity of the hyper-sensitive transition Factor, but not directly related to Eu (Ⅲ) point symmetry.