Figure 1

X-ray diffraction patterns at 295 K and Rietveld refinements of (a) ilmenite ($R_p=0.046$, $R_{wp}=0.067$, and $R_b=0.041$) and (b) perovskite ($R_p=0.031,R_{wp}=0.049$, and $R_b=0.035$) phases.Reuse & Permissions

Figure 2

Polyhedral representations of different polymorphs in comparable orientation.[9] The color of the polyhedra reflects the central cation; (a) and (b) red: Mn, blue: Fe/Sb, (c) blue: Fe, yellow: Sb; Mn polyhedra are omitted for clarity. Small red spheres indicate oxygen atoms.Reuse & Permissions

Figure 3

(Top) Zero-field-cooled (ZFC) and field-cooled (FC) magnetization curves for MFSO in [(a), $H$ $=$ 20 Oe] ilmenite and [(b), $H$ $=$ 3 T] perovskite phases. The magnetization of MFSO perovskite was recorded in a larger field as the low-field magnetic response of the perovskite phase is more affected by minor amounts of magnetic impurities. In that field, ZFC and FC curves closely coincide with each other. The inset shows hysteresis curves [$M$($H$) curves] recorded at $T$ $=$ 10 K for both ilmenite (upper, blue curve) and perovskite (lower, black curve); while a small impurity magnetic moment can be seen in the low-field data of the perovskite, that system displays low-susceptibility linear $M($H$)$ curves. (Bottom) Temperature dependence of the heat capacity $C$ of MFSO in (c) ilmenite and (d) perovskite phases.Reuse & Permissions

Figure 4

(Left) Predicted magnetic structure for (left) ilmenite and (right) perovskite MFSO; (a) side and (b) top views. Mn and Fe atoms are indicated in red and blue colors, respectively. The atoms, forming the primitive cell of Mn${}_2$FeSbO${}_6$, are indicated by numbers. (Middle) Distance dependence of interatomic exchange interactions within Mn and Fe sublattices (squares and triangles, respectively) and between Mn and Fe sublattices (circles); see inset for notation. The interactions between other sites can be obtained by applying the symmetry operations of the space group $P{2}_1/n$.Reuse & Permissions