Neutron diffraction study of the magnetic and structure properties of Co2.50Sb0.50O4 spinel

The Co2.50Sb0.50O4 spinel has been studied by neutron diffraction in the temperature range 10-90 K and at room temperature. The crystal and magnetic structures were solved by the use of the Rietveld method. The cationic distribution was determined to be (Co-1.00(2+))(8a) [Co0.503+Co1.002+Sb0.505+](16d), where 8a and 16d denote tetrahedral and octahedral crystallographic sites, respectively. A collinear ferrimagnetic structure with T-C approximate to 60 K has been found. The obtained Values of magnetic moments of Co2+ ions at 10 K, mu(8a)(Co2+) = 2.6 mu(B) and mu(16d) (Co2+) = 2.9 mu(B), are smaller than expected and we discuss this result. (C) 2000 Elsevier Science B.V. All rights reserved