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Computer-assisted study of the complexation of quinizarin-2-sulphonic acid with iron(III)
1Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada.
Abstract:
A detailed spectrophotometric study of the complexation of iron(III) with quinizarin-2-sulphonic acid (Q) in 0.1M perchloric acid solution is reported. There is evidence that more than one complex exists in the solution. Analyses of the data were made by a PITMAP-type procedure, and comparison of the results from considering several models of solution composition show the preferred model to be that for two complexes with Fe:Q ratios 1:1 and 4:3. Stability constants and calculated spectra for the species are reported. It is suggested that the ligand is bis-chelating in the polynuclear species.
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