Materials Data on SiB2Mo5 by Materials Project
Mo5SiB2 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are two inequivalent Mo2+ sites. In the first Mo2+ site, Mo2+ is bonded to three equivalent B3- and two equivalent Si4- atoms to form MoSi2B3 trigonal bipyramids that share corners with four equivalent MoSi2B4 octahedra, corners with twelve equivalent MoSi2B3 trigonal bipyramids, edges with seven equivalent MoSi2B3 trigonal bipyramids, faces with two equivalent MoSi2B4 octahedra, and a faceface with one MoSi2B3 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 43–61°. There are two shorter (2.34 Å) and one longer (2.41 Å) Mo–B bond lengths. Both Mo–Si bond lengths are 2.58 Å. In the second Mo2+ site, Mo2+ is bonded to four equivalent B3- and two equivalent Si4- atoms to form MoSi2B4 octahedra that share corners with six equivalent MoSi2B4 octahedra, corners with sixteen equivalent MoSi2B3 trigonal bipyramids, and faces with eight equivalent MoSi2B3 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 0–55°. All Mo–B bond lengths are 2.41 Å. Both Mo–Si bond lengths are 2.79 Å. B3- is bonded in a 9-coordinate geometry to eight Mo2+ and one B3- atom. The B–B bond length is 2.07 Å. Si4- is bonded in a 10-coordinate geometry to ten Mo2+ atoms.