Preparation, characterization and properties of some lanthanide oxides

The formation of oxides of the types Ln2O3 and Ln1Ln2O3 is reported. They have been obtained by thermal decomposition of homo- and heterodinuclear complexes of the type Ln2(L)(NO3)4·xH2O or Ln1Ln2(L)(NO3)4·xH2O where H2L is the macrocycle obtained by condensation of 2,6-diformyl-4- chlorophenol and 1,8-diamino-3,6-dioxaoctane. The composition and properties of the oxides, particularly of DyEuO3 and DyNdO3, have been studied by means of X-ray powder diffraction, electron microscopy and X-ray fluorescence techniques together with magnetic investigations. The products obtained have been compared with those prepared by thermal decomposition of the appropriate Ln(NO3)3·xH2O or, where available, with the commercial oxides. The polymorphism of the oxides has been also investigated.