Materials Data on FeCoSb4 by Materials Project
FeCoSb4 crystallizes in the monoclinic P2/m space group. The structure is three-dimensional. Fe3+ is bonded to six Sb+1.25- atoms to form FeSb6 octahedra that share corners with eight equivalent CoSb6 octahedra and edges with two equivalent FeSb6 octahedra. The corner-sharing octahedral tilt angles are 51°. There are two shorter (2.55 Å) and four longer (2.57 Å) Fe–Sb bond lengths. Co2+ is bonded to six Sb+1.25- atoms to form CoSb6 octahedra that share corners with eight equivalent FeSb6 octahedra and edges with two equivalent CoSb6 octahedra. The corner-sharing octahedral tilt angles are 51°. All Co–Sb bond lengths are 2.57 Å. There are two inequivalent Sb+1.25- sites. In the first Sb+1.25- site, Sb+1.25- is bonded in a 4-coordinate geometry to two equivalent Fe3+ and one Co2+ atom. In the second Sb+1.25- site, Sb+1.25- is bonded in a 4-coordinate geometry to one Fe3+ and two equivalent Co2+ atoms.