We report a comprehensive neutron diffraction study of the crystal structure and magnetic order in a series of single-crystal and powder samples of SrFeO3−δ in the vacancy range 0≤δ≤0.23. The data provide detailed insights into the interplay between the oxygen vacancy order and the magnetic structure of this system. In particular, a crystallographic analysis of data on Sr8Fe8O23 revealed a structural transition between the high-temperature tetragonal and a low-temperature monoclinic phase with a critical temperature T = 75 K, which originates from charge ordering on the Fe sublattice and is associated with a metal-insulator transition. Our experiments also revealed a total of seven different magnetic structures of SrFeO3−δ in this range of δ, only two of which (namely an incommensurate helix state in SrFeO3 and a commensurate, collinear antiferromagnetic state in Sr4Fe4O11) had been identified previously. We present a detailed refinement of some of the magnetic ordering patterns and discuss the relationship between the magneto-transport properties of SrFeO3−δ samples and their phase composition and magnetic microstructure.
@article{arxiv.1207.0921,
title = {Neutron diffraction study of spin and charge ordering in SrFeO(3-delta)},
author = {M. Reehuis and C. Ulrich and A. Maljuk and Ch. Niedermayer and B. Ouladdiaf and A. Hoser and T. Hofmann and B. Keimer},
journal= {arXiv preprint arXiv:1207.0921},
year = {2015}
}