Abstract:
Double ferrites ErCaFe2O5.5, ErSrFe2O5.5, and ErBaFe2O5.5 were synthesized by solid_state reac_
tions from erbium and iron(III) oxides and calcium, strontium, and barium carbonates. The compounds were
found to crystallize in the orthorhombic system. Their unit cell parameters were determined by X_ray powder
diffraction; their densities were measured.