Superlattice ordering in SrFeO _3-δ: Electron microscopy and diffraction study

The oxygen-deficient SrFeO _2.74 phase of quenched samples is located within the miscibility gap of the SrFeO _3-δ perovskite system, and exhibits a manifold vacancy ordering pattern at room temperature. We have studied the complex ordering by high-resolution electron microscopy, and by electron and X-ray diffraction. New principal superlattice structures have been identified by electron diffraction which can be of relevance for the electronic and magnetic properties of this respective perovskite system.