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arXiv · 0804.0495

Understanding the Unique Structural and Electronic Properties of SrFeO2

J. M. Pruneda·Jorge Iniguez·Enric Canadell·Hiroshi Kageyama·Mikio Takano
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Abstract

We report a first-principles study of SrFeO$_2$, an infinite-layer oxide with Fe atoms in a perfect square-planar coordination down to essentially 0 K. Our results reveal this striking behavior relies on the double occupation of the 3$d_{z^2}$ orbitals of high-spin Fe$^{2+}$. Such an electronic state results from the hybridization of iron's 3$d_{z^2}$ and 4$s$ orbitals, which enables a large reduction of the intra-atomic exchange splitting of the $z^2$ electrons. The generality of the phenomenon is discussed.

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J. M. Pruneda, Jorge Iniguez, Enric Canadell, Hiroshi Kageyama, Mikio Takano. 2008-04-03. Understanding the Unique Structural and Electronic Properties of SrFeO2. https://doi.org/10.1103/physrevb.78.115101

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