Structural, magnetic and transport characterization of a metallic, ferromagnetic double perovskite with 3d—5d orbital interactions, nominally SrFe1/4Re3/4O3, has been performed. Synchrotron x-ray powder diffraction (SPXD) reveals an orthorhombic structure with an uncommon a+b+c+ Glazer octahedral tilt system (Pnnn, a = 7.87422(4); b = 7.87726(6); c = 7.89795(4)Å; χ2 = 3.125%; Rwp = 8.06%; Rp = 6.47%; 35 variables), with a slight symmetry lowering distortion (P2nn,a = 7.87722(6) Å; b = 7.87433(4)Å; c = 7.89800(4)Å; χ2 = 2.90; Rwp = 7.42; Rp = 6.10; 45 variables). Fe-K-edge and Re L3-edge XANES data support Fe(III) and mixed valent Re(IV/VI). Temperature-dependent magnetic susceptibility reveals ordering near 150 º K and a hysteretic field-dependent magnetization indicates "ferromagnetism" (or ferrimagnetism but with a small, nearly vanishing contribution from the rhenium moment). Ordering of the B-site and the nearly linear B(Fe/Re)-O-B'(Re) bond angles (~170 º) apparently enhance magnetic exchange and (metallic) charge transport near room temperature (ρRT ≈ 2.5 mΩ-cm). A shallow resistivity minimum at 40 º K (ρ40K ≈ 1.9 mΩ-cm) resembling a metal-semiconductor transition is attributed to weak localization.
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