苯甲酸衍生物的Tb(Ⅲ)配合物中配体性质对Tb^(3+)的超灵敏跃迁的影响

Effects of Ligand's Structure on the Hypersensitive Transition of a Series of Complexes of Terbium With Substituted Benzoic Acid

测定了６个苯甲酸衍生物ＲＣ６Ｈ４ＣＯ２Ｈ（Ｒ＝ｏ－ＮＨ２、Ｈ、ｐ－ＮＨ２、ｏ－ＯＨ、ｍ－Ｃｌ、ｏ－ＣＯＯＨ）与铽Ｔｂ（Ⅲ）的二元配合物在３５０ｎｍ紫外光激发下的荧光光谱．结果表明，配合物的荧光强弱顺序为Ｒ＝ｏ－ＮＨ２＞Ｈ＞ｐ－ＮＨ２＞ｏ－ＯＨ＞ｍ－Ｃｌ＞ｏ－ＣＯＯＨ并注意到，标志Ｔｂ３＋的超灵敏跃迁强度的量：蓝光（４９１ｎｍ）与绿光（５４５ｎｍ）的相对强度比（ＩＢ／Ｇ）与配体的酸常数ｐＫａ（Ｌ）及配体的平均极化率α（Ｌ）之间有很好的相关性．定量地探讨了其结构与性能的关系，为进一步探索新型绿色发光材料提供了一定的科学依据．

Quantitative studies, by means of fluorescence spectra and nolinear stepwise regression methods, are reported on the fluorescence properties and electronic effects of a series of complexes of Tb(Ⅲ) with substituted benzoic acid RC 6H 4CO 2H(R= o -NH 2、H、 p -NH 2、 o -OH、 m -Cl、 o -COOH) The quantitative relations between the hypersensitive transition intensity ratio ( I B/G ) and ligand pKa or the mean polarizability of ligand α (L) are as follows, respectively I B/G =-0 364 9+0 632 7 pKa (L)-0 092 9(pKa(L)) 2 ( r =0 950, F =13 82, s =0 026) I B/G =-0 219 5+0 070 8 pKa (L)+0 043 7α(L) ( r =0 889, F =5 66, S =0 038) These show good agreement with the previous experimental results