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arXiv · 1902.06509

Pressure-induced spin-state ordering in Sr$_2$CoO$_3$F

Juan Fernández Afonso·Andrii Sotnikov·Atsushi Hariki·Jan Kuneš
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Abstract

We study theoretically low-temperature phases of a recently synthesized compound Sr$_2$CoO$_3$F under pressure. The analysis combining LDA+DMFT and a strong-coupling effective model points to the existence of not only normal paramagnetic and antiferromagnetic regimes, but also a spin-state ordered phase in a certain range of applied pressure and low temperature. This order is characterized by a checkerboard arrangement of different spin states of cobalt atoms in the lattice.

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Juan Fernández Afonso, Andrii Sotnikov, Atsushi Hariki, Jan Kuneš. 2019-05-14. Pressure-induced spin-state ordering in Sr$_2$CoO$_3$F. https://doi.org/10.1103/physrevb.99.205118

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