Mo4Co2C crystallizes in the cubic Fd-3m space group. There are two inequivalent Mo sites. In the first Mo site, Mo(1) is bonded in a 6-coordinate geometry to six equivalent Co(1) atoms. In the second Mo site, Mo(2) is bonded in a 2-coordinate geometry to four equivalent Co(1) and two equivalent C(1) atoms. Co(1) is bonded in a 12-coordinate geometry to three equivalent Mo(1), six equivalent Mo(2), and three equivalent Co(1) atoms. C(1) is bonded to six equivalent Mo(2) atoms to form corner-sharing CMo6 octahedra. The corner-sharing octahedral tilt angles are 39°.
Mo4Co2C crystallizes in the cubic Fd-3m space group. There are two inequivalent Mo sites. In the first Mo site, Mo(1) is bonded in a 6-coordinate geometry to six equivalent Co(1) atoms. All Mo(1)-Co(1) bond lengths are 2.43 Å. In the second Mo site, Mo(2) is bonded in a 2-coordinate geometry to four equivalent Co(1) and two equivalent C(1) atoms. There are two shorter (2.71 Å) and two longer (2.91 Å) Mo(2)-Co(1) bond lengths. Both Mo(2)-C(1) bond lengths are 2.12 Å. Co(1) is bonded in a 12-coordinate geometry to three equivalent Mo(1), six equivalent Mo(2), and three equivalent Co(1) atoms. All Co(1)-Co(1) bond lengths are 2.60 Å. C(1) is bonded to six equivalent Mo(2) atoms to form corner-sharing CMo6 octahedra. The corner-sharing octahedral tilt angles are 39°.