Stability-charge and stability-structure relationships in the binding of tri- and tetracarboxylic ligands by open-chain polyammonium cations

The interaction of eight polyammonium cations with citrate, 1,2,3-propanetr icarboxylate, and 1,2,3,4-butanetetracarboxylate has been studied potentiom etrically, by using the H+-glass electrode, at 25 degreesC. The stability a nd the speciation of the systems investigated in this work are quite simila r to those found in previous works for several polyammonium-polycarboxylic systems. The formation constants given here, together with several data alr eady reported, have been analyzed to find reliable stability-charge and sta bility-structure relationships.