Ferrimagnetic order in the insulating Sr3Fe2ReO9 double perovskite

A new iron(III)/rhenium(VI) double perovskite oxide, Sr3Fe2ReO9, has been synthesized in polycrystalline form at 1200 °C by solid-state reaction from citrate precursors. The Rietveld analysis of the synchrotron X-ray powder diffraction pattern shows that this compound, at 300 K, has orthorhombic symmetry (S.G.: Immm), with a=5.56733(1) Å, b=5.56796(1) Å and c=7.90224(2) Å. The refinement of the relative Fe/Re occupancies of each B site reveals the presence of a partial cationic order. At high temperatures, the magnetic susceptibility of the Sr3Fe2ReO9 is well described as a paramagnet with ferrimagnetic correlations. Below 450 K, the system displays a spontaneous magnetization, and hysteresis loops are observed.