Coordination of copper(II) to polyaminopolycarboxylic acids in aqueous solution.

The formation of copper(II) complexes in aqueous solution has been followed by EPR and electronic absorption spectroscopy for a series of polyaminopolycarboxylic ligands, namely ethylenediaminotetra-acetic (EDTA), N-(2-hydroxyethyl)ethylenediamino-N,N?,N?-triacetic (HEDTA), ethylenediaminodiacetic (EDDA), iminodiacetic (IDA), and nitrilotriacetic (NTA) acids. The species in complex formation have been identified and structures proposed by previous studies have been examined and discussed on the basis of the spectroscopic data.