First-principles study of the structural, electronic, and magnetic properties of double perovskite Sr<sub>2</sub>FeReO<sub>6</sub> containing various imperfections

First-principles study of the structural, electronic, and magnetic properties of double perovskite Sr₂FeReO₆ containing various imperfections

Zhang Yan^{1, †,}, Duan Li¹, Ji Vincent², Xu Ke-Wei³

Optimized structures of imperfect (marked with circles) Sr₂FeReO₆ of 4 f.u. containing (a) Fe antisite (Fe_Re), one Fe atom substituting for one Re atom at (0.5, 0.5, 0.5) site (Sr₈Fe₅Re₃O₂₄), (b) Re antisite (Re_Fe), one Re atom substituting for one Fe atom at (0, 0.5, 0.5) site (Sr₈Fe₃Re₅O₂₄), (c) Fe1–Re1 interchange (Fe1–Re1), exchanging Fe and Re positions respectively at (0, 0, 0) and (0, 0, 0.5) sites (Sr₈Fe₄Re₄O₂₄), (d) Fe1–Re4 interchange (Fe1–Re4), exchanging Fe and Re positions respectively at (0, 0, 0) and (0.5, 0.5, 0.5) sites (Sr₈Fe₄Mo₄O₂₄), (e) Fe vacancy (V_Fe), removing one Fe atom from (0, 0.5, 0.5) site (Sr₈Fe₃Re₄O₂₄), (f) Re vacancy (V_Re), removing one Re atom from (0.5, 0.5, 0.5) site (Sr₈Fe₄Re₃O₂₄), (g) O vacancy (V_O), removing one O atom from (0.5, 0.5, 0.25) site (Sr₈Fe₄Re₄O₂₃), and (h) Sr vacancy (V_Sr), removing one Sr atom from (0.75, 0.75, 0.75) site (Sr₇Fe₄Re₄O₂₄). The optimized structure of the perfect Sr₂FeReO₆ of 4 f.u. (Sr₈Fe₄Re₄O₂₄) is also shown in panel (i) for comparison.