Synthesis, crystal and magnetic structure of the Ca ₂ Co _1.7 Fe _0.3 O ₅ complex oxide

Complex doped cobaltite Ca 2 Co 1.7 Fe 0.3 O 5 was synthesized using the sol-gel method. The crystal structure of this compound was studied using X-ray diffraction, and it was found to have a solid brownmillerite-type orthorhombic phase with the Pbcm space group. Scanning electron microscopy and small-angle X-ray scattering revealed that the synthesized compound consisted of large grains with an average gyration radius of 832(9) nm. Neutron diffraction was used to determine the structural parameters of the brownmillerite phase as well as the magnetic structure properties. It was found that in the temperature range 10-300 K, the magnetic structure is G-type antiferromagnetic, but below temperature of 200 K, a gradual spin-reorientation phase transition occurs.