混合配位络合物稳定常数的归纳和分析

STUDY ON STABILITY CONSTANTS OF MIXED LIGAND COMPLEXES

络合物稳定常数的测定是密切联系分析分离、无机生化和环境科学等工作的一个课题,已有大量文献报导这方面的工作,所得的数据已有专著详细记载.对于如此大量的实验资料,有必要总结出它的规律性,据以计算未知的络合物稳定常数.为此,我们根据离子极化原理,于1977年提出了一个二元络合物稳定常数的计算式.以后,温元凯等也提出了类似的计算式.随后,我们又将我们的计算式推广使用,并且提出了萃取常数、水解常数、溶度积常数的计算式.

The rule of stability of mixed ligand complexes has been investigated. The stability constants of mixed ligand complexes were calculated by lgK_(MLL')^(ML)=A'Z^2/r+B'x'_(■)+C'+S lgK_(MLL')~M=(A+A')Z^2/r+Bx_(■)+B'x'_(■)+(C+C')+S lgK_(MLL')~M=1/2lgK_(ML_(■)~M)+1/2lgK_(ML'_2)~M+1/2lgX_(■) lgK_(MLL')~M=lgK_(ML)~M+lgK_(ML')~M+S Where lgK_(MLL')~M=[MLL']/[M][L][L'], lgK_(MLL')^(ML)=[MLL']/[ML][L'], S=-λ-λ'+ 1/2lgX_(■), X_(■)=[MLL']~2/[ML_2][ML'_2], λ=1/2(lgK_(ML)~M-lgK_(ML_(■)^(ML)), λ'=1/2(lgK_(ML')~M-lgK_(ML'2)^(ML'), A、B、C、A'、B'、C' are constants, Z is cation charge, r, cation radius, x_(■)= (x_-+x_+)/(x_--x_+), x_- and x_+ are electronegativity values.These equations may be of use in inorganic chemistry and analytical chemistry for predicting approximate values of stability constants of mixed ligand complexes and for choosing suitable organic reagents for metal ions.