镅(Ⅲ)、锔(Ⅲ)的乙二胺二异丙酸二乙酸络合物的稳定常数

STABILITY CONSTANTS OF ETHYLENE DIAMINE DIISOPROPYL DIACETATE COMPLEXES OF Am (Ⅲ) AND Cm (Ⅲ).

摘要: <正> 乙二胺二异丙酸二乙酸(EDDPDA)比乙二胺四乙酸(EDTA)多两个α-甲基。它与Am、Cm的络合研究未见报道。本工作目的在于比较EDDPDA和EDTA同Am、Cm的络合能力,探讨引入两个α-甲基的影响。EDDPDA由本实验室合成,测得其分子量为320.2,熔点为215-216℃,碳、氢和氮的含量分别为44.87％、6.23％和8.69％。

Abstract: The equilibria between Am (Ⅲ), Cm(Ⅲ) and EDDPDAare investigated by a cation exchange method at 25℃ and at a constant ionic strengthμ=0.5. The complex formation of the corresponding EDTA complexes is also studied for comparison. The stability constants are calculated to be:for EDDPDA lg K (Am) =18.10±0.02,lg K (Cm)=18.230±0.02.for EDTA lg K (Am)=17.83±0.01,lg K (Cm)=17.94±0.02.The EDDPDA complexes are more stable owing to the inductive effect of two methyl group alpha to the carboxylates.