【摘要】 本文用¹H NMR和UV VIS光谱技术研究了DPTA与Ca⁺²、Th⁴⁺和抗磁稀土离子Ia³⁺、Lu³⁺、Y³⁺、Sc³⁺的成络作用,发现配体与抗磁稀土离子为慢交换体系,而与Ca²⁺为快交换体系。确定了络合物的组成,Th⁴⁺与试剂生成1:2络合物,Ca²⁺、La³⁺、Lu³⁺、Y³⁺、Sc³⁺主要生成1:1络合物。络合物组成与溶液pH有关。 比较了抗磁稀土离子络合物Δδ和Δλ变化,发现二者随离子半径的变化有相同的规律: Sc³⁺<Y³⁺=Lu³⁺<<La³⁺更多还原

【Abstract】 The complexation of 2,3--dihydroxy--p--xylenediiminotetraacetic acid （DPTA） with Ca²⁺,Th⁴⁺ and diamagnetic rare earth ions La³⁺, Lu³⁺, Y³⁺ and Sc³⁺ has been investigated by ¹HNMR and UV VIS absorption spectroscopy methods in this work. Based on the NMR resultsit is concluded that the reaction of DPTA with the diamagnetic RE ions is a slow exchangereaction, while that with Ca²⁺ is a fast one. The compositions of the complexes are asfollows: Th⁴⁺ with DPTA forms 1:2 complex and the other ions Ca²⁺, La³⁺, Lu³⁺, Y³⁺and Sc³⁺ mainly form 1: 1 complexes. The compositions of the complexes are dependent onthe pH of the solution. The chemical shift variatfons （△δ） on NMR spectra of dismagnetic RE complexes withDPTA have been compared with λ_max variations （△λ） of UV absorption spectra. A similarorder in change was found for both △δ and △λ: Sc³⁺<Y³⁺≈Lu³⁺ <<La³⁺.更多还原