We report on a first-principles study of SrFeO2, an infinite-layer oxide with Fe atoms in a perfect square-planar coordination down to essentially 0 K. Our results reveal that this striking behavior relies on the double occupation of the 3 d z2 orbitals of high-spin Fe2+. Such an electronic state results from electrostatic and hybridization effects, the latter enabling a large reduction in the intra-atomic exchange splitting of the z2 electrons. © 2008 The American Physical Society.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - 2 Sep 2008|