FeSb2O4 crystallizes in the monoclinic P2_1/c space group. Fe(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form edge-sharing FeO6 octahedra. There are two inequivalent Sb sites. In the first Sb site, Sb(1) is bonded in a distorted T-shaped geometry to one O(2), one O(3), and one O(4) atom. In the second Sb site, Sb(2) is bonded in a distorted T-shaped geometry to one O(1), one O(2), and one O(4) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a trigonal non-coplanar geometry to two equivalent Fe(1) and one Sb(2) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Fe(1), one Sb(1), and one Sb(2) atom. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Fe(1) and one Sb(1) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Fe(1), one Sb(1), and one Sb(2) atom.
FeSb2O4 crystallizes in the monoclinic P2_1/c space group. Fe(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form edge-sharing FeO6 octahedra. The Fe(1)-O(2) bond length is 2.20 Å. The Fe(1)-O(4) bond length is 2.17 Å. There is one shorter (2.19 Å) and one longer (2.20 Å) Fe(1)-O(1) bond length. There is one shorter (2.09 Å) and one longer (2.10 Å) Fe(1)-O(3) bond length. There are two inequivalent Sb sites. In the first Sb site, Sb(1) is bonded in a distorted T-shaped geometry to one O(2), one O(3), and one O(4) atom. The Sb(1)-O(2) bond length is 2.02 Å. The Sb(1)-O(3) bond length is 1.98 Å. The Sb(1)-O(4) bond length is 2.02 Å. In the second Sb site, Sb(2) is bonded in a distorted T-shaped geometry to one O(1), one O(2), and one O(4) atom. The Sb(2)-O(1) bond length is 1.96 Å. The Sb(2)-O(2) bond length is 2.04 Å. The Sb(2)-O(4) bond length is 2.04 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a trigonal non-coplanar geometry to two equivalent Fe(1) and one Sb(2) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Fe(1), one Sb(1), and one Sb(2) atom. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Fe(1) and one Sb(1) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Fe(1), one Sb(1), and one Sb(2) atom.