Coordination Compounds as Precursors in the Synthesis of New Materials

Macrocyclic and macroacyclic polynucleating compartmental ligands have been prepared by condensation of 2,6-diformyl-4-chlorophenol and 1,8-diamino-3,6-dioxaoctane or 2,3-dihydroxybenzaldehyde with the ethylenediamine. These ligands, produce, by reaction under suitable conditions, homo and heterodinuclear complexes, containing d and/or f metal ions and/or barium which have been characterized also by x-ray diffractometry. These complexes have been used as useful precursors in the formation of crystallographically pure mixed oxides by their thermal decomposition. The composition and the properties of these oxides have been studied by x-ray powder diffraction, electron microscopy and x-ray fluorescence techniques together with magnetic and optical investigations.