一种同时测定多核配离子种类和稳定常数的简便方法

摘要

针对现有测定多核配合物稳定常数的方法大多较为复杂的情形,提出了一种利用多核配离子最大分布系数来测定稳定常数的新方法,本法原理和计算简单,无需编程,并可确定溶液中存在的多核配离子种类.文章使用溶液中金属离子总浓度对数值对自由金属离子浓度负对数和自由配体浓度负对数的一阶偏微分值以及因素轮换法来确定稳定常数测定时的实验条件.镍离子与三乙醇胺以及镍离子与乙醇胺两种多核配合物体系被用于验证本文公式,计算结果与真值一致.%To avoid the complexity of existing stability constant determination methods for polynuclear complexes, we presented a new determination method by using the maximum distribution coefficients of polynuclear complex ions. This method works with simple principle and calculation, needs no programming, and can determine the stoichiometry of polynuclear complex ions existing in solution. We employed the first-order partial differentials, logarithmic value of total metal concentration in solution against negative logarithmic values of free metal concentration and that against free ligand concentration, and the factor alternation method to obtain experimental conditions for determining the stability constant. Computational results of two polynuclear complexes, which were used to verify the acquired formula, are in accordance with real values.