CoSeO4 crystallizes in the orthorhombic Cmcm space group. Co(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form CoO6 octahedra that share corners with six equivalent Se(1)O4 tetrahedra and edges with two equivalent Co(1)O6 octahedra. Se(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form SeO4 tetrahedra that share corners with six equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 51-55°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Co(1) and one Se(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Co(1) and one Se(1) atom.
CoSeO4 crystallizes in the orthorhombic Cmcm space group. Co(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form CoO6 octahedra that share corners with six equivalent Se(1)O4 tetrahedra and edges with two equivalent Co(1)O6 octahedra. Both Co(1)-O(1) bond lengths are 1.98 Å. All Co(1)-O(2) bond lengths are 2.14 Å. Se(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form SeO4 tetrahedra that share corners with six equivalent Co(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 51-55°. Both Se(1)-O(1) bond lengths are 1.65 Å. Both Se(1)-O(2) bond lengths are 1.68 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one Co(1) and one Se(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Co(1) and one Se(1) atom.