ThCo5 crystallizes in the hexagonal P6/mmm space group. Th(1) is bonded in a 18-coordinate geometry to six equivalent Co(1) and twelve equivalent Co(2) atoms. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to three equivalent Th(1) and six equivalent Co(2) atoms to form distorted CoTh3Co6 cuboctahedra that share corners with twelve equivalent Co(2)Th4Co8 cuboctahedra, corners with fifteen equivalent Co(1)Th3Co6 cuboctahedra, edges with twelve equivalent Co(2)Th4Co8 cuboctahedra, faces with five equivalent Co(1)Th3Co6 cuboctahedra, and faces with six equivalent Co(2)Th4Co8 cuboctahedra. In the second Co site, Co(2) is bonded to four equivalent Th(1), four equivalent Co(1), and four equivalent Co(2) atoms to form CoTh4Co8 cuboctahedra that share corners with eight equivalent Co(1)Th3Co6 cuboctahedra, corners with sixteen equivalent Co(2)Th4Co8 cuboctahedra, edges with eight equivalent Co(1)Th3Co6 cuboctahedra, edges with ten equivalent Co(2)Th4Co8 cuboctahedra, faces with four equivalent Co(1)Th3Co6 cuboctahedra, and faces with ten equivalent Co(2)Th4Co8 cuboctahedra.
ThCo5 crystallizes in the hexagonal P6/mmm space group. Th(1) is bonded in a 18-coordinate geometry to six equivalent Co(1) and twelve equivalent Co(2) atoms. All Th(1)-Co(1) bond lengths are 2.86 Å. All Th(1)-Co(2) bond lengths are 3.18 Å. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to three equivalent Th(1) and six equivalent Co(2) atoms to form distorted CoTh3Co6 cuboctahedra that share corners with twelve equivalent Co(2)Th4Co8 cuboctahedra, corners with fifteen equivalent Co(1)Th3Co6 cuboctahedra, edges with twelve equivalent Co(2)Th4Co8 cuboctahedra, faces with five equivalent Co(1)Th3Co6 cuboctahedra, and faces with six equivalent Co(2)Th4Co8 cuboctahedra. All Co(1)-Co(2) bond lengths are 2.45 Å. In the second Co site, Co(2) is bonded to four equivalent Th(1), four equivalent Co(1), and four equivalent Co(2) atoms to form CoTh4Co8 cuboctahedra that share corners with eight equivalent Co(1)Th3Co6 cuboctahedra, corners with sixteen equivalent Co(2)Th4Co8 cuboctahedra, edges with eight equivalent Co(1)Th3Co6 cuboctahedra, edges with ten equivalent Co(2)Th4Co8 cuboctahedra, faces with four equivalent Co(1)Th3Co6 cuboctahedra, and faces with ten equivalent Co(2)Th4Co8 cuboctahedra. All Co(2)-Co(2) bond lengths are 2.47 Å.