Mo3Co2 crystallizes in the monoclinic P2_1/m space group. There are three inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to three equivalent Mo(2), three equivalent Mo(3), two equivalent Co(1), and four equivalent Co(2) atoms to form distorted MoCo6Mo6 cuboctahedra that share corners with five equivalent Co(1)Co3Mo9 cuboctahedra, corners with five equivalent Co(2)Co3Mo9 cuboctahedra, edges with two equivalent Co(2)Co3Mo9 cuboctahedra, edges with four equivalent Co(1)Co3Mo9 cuboctahedra, edges with six equivalent Mo(1)Co6Mo6 cuboctahedra, faces with four equivalent Mo(1)Co6Mo6 cuboctahedra, faces with four equivalent Co(1)Co3Mo9 cuboctahedra, and faces with four equivalent Co(2)Co3Mo9 cuboctahedra. In the second Mo site, Mo(2) is bonded in a 11-coordinate geometry to two equivalent Mo(3), three equivalent Mo(1), three equivalent Co(1), and four equivalent Co(2) atoms. In the third Mo site, Mo(3) is bonded in a 12-coordinate geometry to two equivalent Mo(2), two equivalent Mo(3), three equivalent Mo(1), one Co(2), and four equivalent Co(1) atoms. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to two equivalent Mo(1), three equivalent Mo(2), four equivalent Mo(3), one Co(2), and two equivalent Co(1) atoms to form distorted CoCo3Mo9 cuboctahedra that share corners with four equivalent Co(2)Co3Mo9 cuboctahedra, corners with five equivalent Mo(1)Co6Mo6 cuboctahedra, edges with four equivalent Mo(1)Co6Mo6 cuboctahedra, edges with four equivalent Co(1)Co3Mo9 cuboctahedra, edges with six equivalent Co(2)Co3Mo9 cuboctahedra, faces with three equivalent Co(2)Co3Mo9 cuboctahedra, faces with four equivalent Mo(1)Co6Mo6 cuboctahedra, and faces with four equivalent Co(1)Co3Mo9 cuboctahedra. In the second Co site, Co(2) is bonded to one Mo(3), four equivalent Mo(1), four equivalent Mo(2), one Co(1), and two equivalent Co(2) atoms to form distorted CoCo3Mo9 cuboctahedra that share corners with four equivalent Co(1)Co3Mo9 cuboctahedra, corners with five equivalent Mo(1)Co6Mo6 cuboctahedra, edges with two equivalent Mo(1)Co6Mo6 cuboctahedra, edges with two equivalent Co(2)Co3Mo9 cuboctahedra, edges with six equivalent Co(1)Co3Mo9 cuboctahedra, faces with three equivalent Co(1)Co3Mo9 cuboctahedra, faces with four equivalent Mo(1)Co6Mo6 cuboctahedra, and faces with six equivalent Co(2)Co3Mo9 cuboctahedra.
Mo3Co2 crystallizes in the monoclinic P2_1/m space group. There are three inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to three equivalent Mo(2), three equivalent Mo(3), two equivalent Co(1), and four equivalent Co(2) atoms to form distorted MoCo6Mo6 cuboctahedra that share corners with five equivalent Co(1)Co3Mo9 cuboctahedra, corners with five equivalent Co(2)Co3Mo9 cuboctahedra, edges with two equivalent Co(2)Co3Mo9 cuboctahedra, edges with four equivalent Co(1)Co3Mo9 cuboctahedra, edges with six equivalent Mo(1)Co6Mo6 cuboctahedra, faces with four equivalent Mo(1)Co6Mo6 cuboctahedra, faces with four equivalent Co(1)Co3Mo9 cuboctahedra, and faces with four equivalent Co(2)Co3Mo9 cuboctahedra. There is one shorter (2.64 Å) and two longer (2.67 Å) Mo(1)-Mo(2) bond lengths. There is one shorter (2.62 Å) and two longer (2.66 Å) Mo(1)-Mo(3) bond lengths. There is one shorter (2.64 Å) and one longer (2.80 Å) Mo(1)-Co(1) bond length. There are a spread of Mo(1)-Co(2) bond distances ranging from 2.71-2.84 Å. In the second Mo site, Mo(2) is bonded in a 11-coordinate geometry to two equivalent Mo(3), three equivalent Mo(1), three equivalent Co(1), and four equivalent Co(2) atoms. There is one shorter (2.62 Å) and one longer (3.02 Å) Mo(2)-Mo(3) bond length. There are two shorter (2.78 Å) and one longer (2.80 Å) Mo(2)-Co(1) bond length. There are a spread of Mo(2)-Co(2) bond distances ranging from 2.56-2.83 Å. In the third Mo site, Mo(3) is bonded in a 12-coordinate geometry to two equivalent Mo(2), two equivalent Mo(3), three equivalent Mo(1), one Co(2), and four equivalent Co(1) atoms. Both Mo(3)-Mo(3) bond lengths are 2.89 Å. The Mo(3)-Co(2) bond length is 2.74 Å. There are a spread of Mo(3)-Co(1) bond distances ranging from 2.57-2.95 Å. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to two equivalent Mo(1), three equivalent Mo(2), four equivalent Mo(3), one Co(2), and two equivalent Co(1) atoms to form distorted CoCo3Mo9 cuboctahedra that share corners with four equivalent Co(2)Co3Mo9 cuboctahedra, corners with five equivalent Mo(1)Co6Mo6 cuboctahedra, edges with four equivalent Mo(1)Co6Mo6 cuboctahedra, edges with four equivalent Co(1)Co3Mo9 cuboctahedra, edges with six equivalent Co(2)Co3Mo9 cuboctahedra, faces with three equivalent Co(2)Co3Mo9 cuboctahedra, faces with four equivalent Mo(1)Co6Mo6 cuboctahedra, and faces with four equivalent Co(1)Co3Mo9 cuboctahedra. The Co(1)-Co(2) bond length is 2.62 Å. Both Co(1)-Co(1) bond lengths are 2.60 Å. In the second Co site, Co(2) is bonded to one Mo(3), four equivalent Mo(1), four equivalent Mo(2), one Co(1), and two equivalent Co(2) atoms to form distorted CoCo3Mo9 cuboctahedra that share corners with four equivalent Co(1)Co3Mo9 cuboctahedra, corners with five equivalent Mo(1)Co6Mo6 cuboctahedra, edges with two equivalent Mo(1)Co6Mo6 cuboctahedra, edges with two equivalent Co(2)Co3Mo9 cuboctahedra, edges with six equivalent Co(1)Co3Mo9 cuboctahedra, faces with three equivalent Co(1)Co3Mo9 cuboctahedra, faces with four equivalent Mo(1)Co6Mo6 cuboctahedra, and faces with six equivalent Co(2)Co3Mo9 cuboctahedra. Both Co(2)-Co(2) bond lengths are 2.68 Å.