ThCe crystallizes in the trigonal R-3m space group. Th(1) is bonded to six equivalent Th(1) and six equivalent Ce(1) atoms to form ThCe6Th6 cuboctahedra that share corners with twelve equivalent Th(1)Ce6Th6 cuboctahedra, edges with twelve equivalent Th(1)Ce6Th6 cuboctahedra, edges with twelve equivalent Ce(1)Ce6Th6 cuboctahedra, faces with six equivalent Th(1)Ce6Th6 cuboctahedra, and faces with twelve equivalent Ce(1)Ce6Th6 cuboctahedra. Ce(1) is bonded to six equivalent Th(1) and six equivalent Ce(1) atoms to form CeCe6Th6 cuboctahedra that share corners with twelve equivalent Ce(1)Ce6Th6 cuboctahedra, edges with twelve equivalent Th(1)Ce6Th6 cuboctahedra, edges with twelve equivalent Ce(1)Ce6Th6 cuboctahedra, faces with six equivalent Ce(1)Ce6Th6 cuboctahedra, and faces with twelve equivalent Th(1)Ce6Th6 cuboctahedra.
ThCe crystallizes in the trigonal R-3m space group. Th(1) is bonded to six equivalent Th(1) and six equivalent Ce(1) atoms to form ThCe6Th6 cuboctahedra that share corners with twelve equivalent Th(1)Ce6Th6 cuboctahedra, edges with twelve equivalent Th(1)Ce6Th6 cuboctahedra, edges with twelve equivalent Ce(1)Ce6Th6 cuboctahedra, faces with six equivalent Th(1)Ce6Th6 cuboctahedra, and faces with twelve equivalent Ce(1)Ce6Th6 cuboctahedra. All Th(1)-Th(1) bond lengths are 3.48 Å. All Th(1)-Ce(1) bond lengths are 3.45 Å. Ce(1) is bonded to six equivalent Th(1) and six equivalent Ce(1) atoms to form CeCe6Th6 cuboctahedra that share corners with twelve equivalent Ce(1)Ce6Th6 cuboctahedra, edges with twelve equivalent Th(1)Ce6Th6 cuboctahedra, edges with twelve equivalent Ce(1)Ce6Th6 cuboctahedra, faces with six equivalent Ce(1)Ce6Th6 cuboctahedra, and faces with twelve equivalent Th(1)Ce6Th6 cuboctahedra. All Ce(1)-Ce(1) bond lengths are 3.48 Å.