The stability constants for mixed binuclear complex formation in aqueous solution between Iron(IlI}-EDT A complex and various ligands, thiocyanate and hexacyanofenate(lI), have been obtained from spectrophotometric measurements. The results can be interpreted to obtain the evidence that the Iron(I1I}-EDTA complex is predominantly six-coordinated and hexadentate in solution.


W C E HIGGINSON ,A H KHAN ,