Resumen

PENA, O. et al. Magnetic properties of spinel-type oxides NiMn_2-xMe_xO₄. J. Chil. Chem. Soc. [online]. 2005, vol.50, n.3, pp.617-623. ISSN 0717-9707.  http://dx.doi.org/10.4067/S0717-97072005000300016.

New materials, based on the well-known spinel compound NiMn₂O₄, have been synthesized and characterized from the magnetic point of view. The manganese cation was partially substituted in the general formula NiMn_2-xMe_xO₄ , by nonmagnetic and magnetic elements, such as Me = Ga, Zn, Ni and Cr (0 x 1). Prior to the determination of their magnetic properties, the non-substituted spinel NiMn₂O₄ was carefully characterized and studied as a function of the oxygen stoichiometry, based on the influence of the annealing atmosphere and quenching rate. The ferrimagnetic character was observed in all samples, with a paramagnetic-to-ferromagnetic transition temperature T_c stabilized at 110 K, and well defined long-range antiferromagnetic interactions at lower temperatures, which depend on the applied field and the substitute concentration

Palabras clave : magnetic oxides; spinels; magnetic exchange; ferrimagnetic properties.