Modulation of the Physicochemical Properties of Heteropolynuclear Assemblies Containing Lanthanide Ions and 2,2′‐oxydiacetate

This work focuses on the polynuclear complexes formed by a lanthanide ion (Ln), a bivalent cation (M) and oxydiacetate (oda) as bridging ligand, with general formula [Ln(2)M(3)(oda)(6)(H2O)(6)]center dot xH(2)O. The complexes can adopt more than one polymorphic structure, being the hexagonal (P6/mcc) and cubic (Fd3c) the most noticeable, as determined by x-ray powder diffraction. The influence of Ln and M on the solid-state structure is discussed. In addition, potentiometric studies are performed to support the existence of polynuclear species in solution.