稀土茜素黄R配合物的合成、表征及荧光性质

Studies on the Preparation, Characterization and Fluorescence Property of Rare Earth with Alizarin Yellow R

合成了 4种茜素黄R稀土配合物 ,通过对元素分析、红外光谱、紫外光谱和核磁共振氢谱的分析 ,确定它们的组成为 :Na[REL2 ]·2H2 O(RE =Sm ,Eu ,Tb ,Y ,NaHL =茜素黄R)。红外光谱表明 :配体以羧羰基的氧与稀土离子以单齿配位 ;配体的酚羟基离解 ,脱去质子后羟基氧与稀土离子配位 ;即酚氧和羧羰基的氧与稀土离子形成一个六元螯合环。配体的吸收峰 398nm在形成配合物后移于 35 1～ 35 5nm ,发生了较大位移 ,这说明稀土离子与配体成键 ;配合物IR在 4 15～ 4 35cm-1之间出现的新吸收峰归属为RE—O键的伸缩振动 ,佐证了配合物的形成 ;硝基中的氧和偶氮的氮原子未参与配位 ;IR还说明有两个水分子配位于稀土离子。紫外灯下可以看到Eu(Ⅲ )的配合物很强的红色荧光 ;荧光光谱测定 :Na[EuL2 ]·2H2 O有两个荧光发射峰分属于Eu的 5D0 → 7F1和5D0 → 7F2 跃迁。

Four rare earth complexes with alizarin yellow R have been prepared and characterized by elemental analysis, IR, UV and H-1 NMR in this paper. Their general formula was determined as the following Na[REL2].2H(2)O(RE = Sm, Eu, Tb, Y. NaHL = alizarin yellow R). The IR shows that the phenolic proton dissociates and the phenolic oxygen atom is coordinated to metals. The carboxylic oxygen atom is coordinated to metals by single dentate. The phenolic oxygen atom together with carboxylic oxygen atom chelates with ion forming a six-mumber ring. Two water molecules are coordinated to rare earth ion. The spectrum of the ligand shows that a band at 398 nm is shifted to 351-355 mn in the complexes showing that the carbonyl oxygen and phenolic oxygen atom are coordinated to the metal ion. The oxygen atom of group -NO2 and nitrogen atom of -N-N- do not bind to metal ions. The strong red fluorescence of Eu(III) complexes is observed in the light of fluorescence lamp. Two strong fluorescence peaks of complex Na [EuL2].2H(2)O may be attributed to the fluorescence spectra of D-5(0) --> F-7(1) and D-5(0) --> F-7(2) transitions of Eu3+.