INVESTIGATION OF COPPER(Ⅱ)-ETHYLENEDIAMINETETRAACETATE COMPLEXATION BY WINDOW FACTOR ANALYSIS OF ULTRAVIOLET SPECTRA

Window factor analysis(WFA)is a self-modeling chemometric technique for obtaining the concentrationprofiles of components from evolutionary processes such as chromotography,titrations and reactionkinetics.By specifying the‘window’,i.e.the region along the evolutionary axis indigenous to acomponent,the concentration profile of the component can be obtained without recourse to anyinformation concerning the other components.Mathematical expressions required to perform suchcomputations are derived.The method is applied to the investigation of copper(Ⅱ)complexation withethylenediaminetetraacetate(EDTA)by recording and factor analyzing the ultraviolet spectra of aqueoussolutions containing a fixed amount of the disodium salt of EDTA and varying amounts of CuCl_2.Evidence for four different species of EDTA is obtained.Clues concerning the stoichiometry of thespecies are garnered from the concentration profiles.