XAS studies on Cu(II) complexes with derivatives of phenoxyacetic and benzoic acids

The geometry of metal–ligand interaction of three Cu(II) complexes with carboxylic acids has been determined by X-ray absorption spectroscopy. Around Cu(II) cation in a complex with 4-methoxy-3-nitrobenzoate anion a square geometry is formed by the carboxylate groups from two monodentate ligands and two water molecules. The tetragonal pyramid around Cu(II) composed by two carboxylate groups from two monodentate ligands and three water molecules is observed for 2-methoxyphenoxyacetate complex. The 4-chlorophenoxyacetate complex with Cu(II) exhibits tetragonal-bipyramidal geometry, with two carboxylate and two ether oxygen atoms from bidentate ligands and two water molecules in the coordination sphere.