Mo5SiB2 crystallizes in the tetragonal I4/mcm space group. There are two inequivalent Mo sites. In the first Mo site, Mo(2) is bonded to two equivalent Mo(1), three equivalent B(1), and two equivalent Si(1) atoms to form a mixture of distorted edge, face, and corner-sharing MoSi2B3Mo2 trigonal bipyramids. In the second Mo site, Mo(1) is bonded in a 14-coordinate geometry to eight equivalent Mo(2), four equivalent B(1), and two equivalent Si(1) atoms. B(1) is bonded in a 9-coordinate geometry to two equivalent Mo(1), six equivalent Mo(2), and one B(1) atom. Si(1) is bonded in a 10-coordinate geometry to two equivalent Mo(1) and eight equivalent Mo(2) atoms.
Mo5SiB2 crystallizes in the tetragonal I4/mcm space group. There are two inequivalent Mo sites. In the first Mo site, Mo(2) is bonded to two equivalent Mo(1), three equivalent B(1), and two equivalent Si(1) atoms to form a mixture of distorted edge, face, and corner-sharing MoSi2B3Mo2 trigonal bipyramids. Both Mo(2)-Mo(1) bond lengths are 2.75 Å. There are two shorter (2.34 Å) and one longer (2.41 Å) Mo(2)-B(1) bond length. Both Mo(2)-Si(1) bond lengths are 2.58 Å. In the second Mo site, Mo(1) is bonded in a 14-coordinate geometry to eight equivalent Mo(2), four equivalent B(1), and two equivalent Si(1) atoms. All Mo(1)-B(1) bond lengths are 2.41 Å. Both Mo(1)-Si(1) bond lengths are 2.79 Å. B(1) is bonded in a 9-coordinate geometry to two equivalent Mo(1), six equivalent Mo(2), and one B(1) atom. The B(1)-B(1) bond length is 2.07 Å. Si(1) is bonded in a 10-coordinate geometry to two equivalent Mo(1) and eight equivalent Mo(2) atoms.