Th2CeO6 is Fluorite-derived structured and crystallizes in the orthorhombic Immm space group. Th(1) is bonded in a body-centered cubic geometry to two equivalent O(2) and six equivalent O(1) atoms. Ce(1) is bonded in a body-centered cubic geometry to four equivalent O(1) and four equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Th(1) and one Ce(1) atom to form OCeTh3 tetrahedra that share corners with six equivalent O(2)Ce2Th2 tetrahedra, corners with ten equivalent O(1)CeTh3 tetrahedra, edges with two equivalent O(2)Ce2Th2 tetrahedra, and edges with four equivalent O(1)CeTh3 tetrahedra. In the second O site, O(2) is bonded to two equivalent Th(1) and two equivalent Ce(1) atoms to form OCe2Th2 tetrahedra that share corners with four equivalent O(2)Ce2Th2 tetrahedra, corners with twelve equivalent O(1)CeTh3 tetrahedra, edges with two equivalent O(2)Ce2Th2 tetrahedra, and edges with four equivalent O(1)CeTh3 tetrahedra.
Th2CeO6 is Fluorite-derived structured and crystallizes in the orthorhombic Immm space group. Th(1) is bonded in a body-centered cubic geometry to two equivalent O(2) and six equivalent O(1) atoms. Both Th(1)-O(2) bond lengths are 2.41 Å. There are four shorter (2.41 Å) and two longer (2.42 Å) Th(1)-O(1) bond lengths. Ce(1) is bonded in a body-centered cubic geometry to four equivalent O(1) and four equivalent O(2) atoms. All Ce(1)-O(1) bond lengths are 2.37 Å. All Ce(1)-O(2) bond lengths are 2.39 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Th(1) and one Ce(1) atom to form OCeTh3 tetrahedra that share corners with six equivalent O(2)Ce2Th2 tetrahedra, corners with ten equivalent O(1)CeTh3 tetrahedra, edges with two equivalent O(2)Ce2Th2 tetrahedra, and edges with four equivalent O(1)CeTh3 tetrahedra. In the second O site, O(2) is bonded to two equivalent Th(1) and two equivalent Ce(1) atoms to form OCe2Th2 tetrahedra that share corners with four equivalent O(2)Ce2Th2 tetrahedra, corners with twelve equivalent O(1)CeTh3 tetrahedra, edges with two equivalent O(2)Ce2Th2 tetrahedra, and edges with four equivalent O(1)CeTh3 tetrahedra.