Ca(WO2)2 crystallizes in the orthorhombic Imma space group. Ca(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form CaO6 octahedra that share corners with six equivalent W(1)O4 tetrahedra, edges with two equivalent Ca(1)O6 octahedra, and edges with four equivalent W(2)O6 octahedra. There are two inequivalent W sites. In the first W site, W(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form WO4 tetrahedra that share corners with six equivalent Ca(1)O6 octahedra and corners with six equivalent W(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-71°. In the second W site, W(2) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form WO6 octahedra that share corners with six equivalent W(1)O4 tetrahedra, edges with two equivalent W(2)O6 octahedra, and edges with four equivalent Ca(1)O6 octahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to two equivalent Ca(1), one W(1), and one W(2) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Ca(1), one W(1), and two equivalent W(2) atoms.
Ca(WO2)2 crystallizes in the orthorhombic Imma space group. Ca(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form CaO6 octahedra that share corners with six equivalent W(1)O4 tetrahedra, edges with two equivalent Ca(1)O6 octahedra, and edges with four equivalent W(2)O6 octahedra. Both Ca(1)-O(2) bond lengths are 2.40 Å. All Ca(1)-O(1) bond lengths are 2.34 Å. There are two inequivalent W sites. In the first W site, W(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form WO4 tetrahedra that share corners with six equivalent Ca(1)O6 octahedra and corners with six equivalent W(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-71°. Both W(1)-O(1) bond lengths are 2.12 Å. Both W(1)-O(2) bond lengths are 2.07 Å. In the second W site, W(2) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form WO6 octahedra that share corners with six equivalent W(1)O4 tetrahedra, edges with two equivalent W(2)O6 octahedra, and edges with four equivalent Ca(1)O6 octahedra. Both W(2)-O(1) bond lengths are 2.18 Å. All W(2)-O(2) bond lengths are 2.18 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to two equivalent Ca(1), one W(1), and one W(2) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Ca(1), one W(1), and two equivalent W(2) atoms.