TITLE:
Study of the Crystallographic and Magnetic Structure in the Nickel Substituted Cobalt Ferrites by Neutron Diffraction
AUTHORS:
Sadia Khanam, A. K. M. Zakaria, M. H. Ahsan, T. K. Datta, S. Aktar, S. I. Liba, S. Hossain, A. K. Das, I. Kamal, S. M. Yunus, D. K. Saha, S.-G. Eriksson
KEYWORDS:
Ferrites, Spinel Structure, Crystal Structure, Neutron Diffraction, Ferrimagnetic
JOURNAL NAME:
Materials Sciences and Applications,
Vol.6 No.4,
April
21,
2015
ABSTRACT: The polycrystalline spinel oxides NiXCo1-XFe2O4 with composition x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0
were prepared by conventional solid state ceramic sintering technique in air at 1300°C. X-ray diffraction
experiments were carried out on all the samples at room temperature in order to characterize
the materials. X-ray diffraction patterns showed sharp peaks indicating the formation of
single phase cubic spinel structure. The neutron diffraction experiments were performed on all
samples at room temperature, with an incident monochromatic neutron beam of wavelength λ =
1.5656 Å. The experimental neutron diffraction data were analyzed using the computer program
FullProf in the Reitveld method. Reitveld refinement of the neutron diffraction data reveals that
the samples possess cubic symmetry corresponding to the space group F d-3m. Cation distribution
between the two sublattices of the spinel structure has been found from the analysis of the neutron
diffraction data. Lattice parameters, oxygen position parameters, and overall temperature
factors have also been determined from the analysis of neutron diffraction data. The lattice parameter
decreases and oxygen position parameter increases with increasing Ni content in the system.
Sublattices and net magnetic moments have been determined from the refinement of neutron
diffraction data. The magnetic structure at room temperature was found to be ferrimagnetic for all
the samples.