Thermal expansion and cation partitioning of MnFe₂O₄ (Jacobsite) from 1.6 to 1276 K studied by using neutron powder diffraction

MnFe₂O₄ is a low-cost and stable magnetic spinel ferrite. In this phase, the influence of the inversion degree on the magnetic properties is still not well understood. To understand this relationship, Mn-ferrite was synthesized by a chemical co-precipitation method modified in our laboratory and studied by using the Neutron Powder Diffraction from 1.6 K to 1243 K. A full refinement of both crystal and magnetic structures was performed in order to correlate the high-temperature cation partitioning, the Curie transition and the structure changes of the Mn-ferrite. In this work three main temperature intervals are detected, characterized by different Mn-ferrite behaviors: first, ranging from 1.6 K to 573 K, where MnFe₂O₄ is magnetic; second, from 573 K to 623 K, where MnFe₂O₄ becomes paramagnetic without cation partitioning; and lastly, from 673 K to 1243 K, where cation partitioning occurs.