Structural and magnetic study of the double‐perovskites Ba ₂ (Fe, B′) ₂ O ₆ (B′ = Mo, W and Re)

Abstract

Ceramics of Ba 2 (Fe,B') 2 O 6 double-perovskites have been prepared and studied for B' = Mo, W and Re. Rietveld analysis confirms that all samples crystallize in a cubic double-perovskite structure with Fm 3 m space group. Magnetization measurements performed in the temperature range from 5 K to 350 K show a ferromagnetic behaviour for both materials Ba 2 (Fe,Mo) 2 O 6 and Ba 2 (Fe,Re) 2 O 6 , with T C = 335 K, 318 K respectively, and antiferromagnetic behaviour for Ba 2 (Fe,W) 2 O 6 with T N = 20 K.

Tuning magnetic coercivity with external pressure in iron-rhenium based ferrimagnetic double perovskites

“…A case in point is that of double perovskites A 2 FeReO 6 (A = Ba, Sr and Ca) and Sr 2 FeMoO 6 , which are ferrimagnets with high degree of spin polarization of conduction/valence electrons and high magnetic ordering tem-perature (300-550 K) [29][30][31][32][33][34] , hence good candidate materials for use as spin polarizers/analyzers in spintronic devices [35][36][37][38] . A major difference in magnetic properties in going from Mo (second row, 4d element) to Re (third row 5d element) at B sites is that the Re-based double perovskites are magnetically hard while the Mo-based double perovskites are magnetically soft 29,[39][40][41] . This points to the importance of spin-orbit interactions in the heavy Re ions and identifies the Re sublattice as the dominant source of magnetic anisotropy in the Re-based double perovskites which are the focus of the current study.…”

Structural Disorder and Classical Spin-Glass Behaviour in Ba3Fe2SbO9

“…4 (M ¼ W, Mo, Re, Nb, Ta, U) are cubic. [9,10] Ba 3 Fe 2 ReO 9 and Ba 3 Fe 2 TeO 9 are reported as hexagonal [3,8] but Ba 3 Fe 2 UO 9 as cubic. [11] The favourability of either the cubic or hexagonal structure in each case is well predicted by the Goldschmidt tolerance factor…”