DOI: 10.17188/1283863
title: Materials Data on Ba21(Cd2Sb9)2 by Materials Project

description: Ba21Cd4Sb18 crystallizes in the orthorhombic Cmce space group. The structure is three-dimensional. there are twelve inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to six Sb+2.78- atoms. There are a spread of Ba–Sb bond distances ranging from 3.38–4.18 Å. In the second Ba2+ site, Ba2+ is bonded to six Sb+2.78- atoms to form distorted BaSb6 octahedra that share corners with five BaSb6 octahedra, corners with five BaSb7 pentagonal bipyramids, corners with three CdSb4 tetrahedra, edges with three BaSb6 octahedra, an edgeedge with one CdSb4 tetrahedra, a faceface with one BaSb6 octahedra, and faces with two BaSb7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 37–51°. There are a spread of Ba–Sb bond distances ranging from 3.44–3.89 Å. In the third Ba2+ site, Ba2+ is bonded to six Sb+2.78- atoms to form distorted BaSb6 octahedra that share corners with six BaSb6 octahedra, corners with two BaSb7 pentagonal bipyramids, corners with two CdSb4 tetrahedra, an edgeedge with one BaSb6 octahedra, an edgeedge with one CdSb4 tetrahedra, faces with two BaSb6 octahedra, faces with three BaSb7 pentagonal bipyramids, and a faceface with one CdSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 40–53°. There are a spread of Ba–Sb bond distances ranging from 3.49–3.76 Å. In the fourth Ba2+ site, Ba2+ is bonded to six Sb+2.78- atoms to form distorted BaSb6 octahedra that share corners with six BaSb6 octahedra, corners with two BaSb7 pentagonal bipyramids, corners with two CdSb4 tetrahedra, edges with three BaSb6 octahedra, edges with two CdSb4 tetrahedra, faces with two BaSb6 octahedra, and a faceface with one BaSb7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 34–61°. There are a spread of Ba–Sb bond distances ranging from 3.42–3.76 Å. In the fifth Ba2+ site, Ba2+ is bonded to six Sb+2.78- atoms to form BaSb6 octahedra that share corners with eight BaSb6 octahedra, corners with two BaSb7 pentagonal bipyramids, corners with three CdSb4 tetrahedra, edges with two equivalent BaSb6 octahedra, faces with three BaSb6 octahedra, and a faceface with one BaSb7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 33–61°. There are a spread of Ba–Sb bond distances ranging from 3.53–3.74 Å. In the sixth Ba2+ site, Ba2+ is bonded in a 7-coordinate geometry to seven Sb+2.78- atoms. There are a spread of Ba–Sb bond distances ranging from 3.48–4.19 Å. In the seventh Ba2+ site, Ba2+ is bonded to seven Sb+2.78- atoms to form distorted BaSb7 pentagonal bipyramids that share corners with eight BaSb6 octahedra, corners with two CdSb4 tetrahedra, an edgeedge with one BaSb7 pentagonal bipyramid, faces with six BaSb6 octahedra, and faces with two equivalent CdSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 39–57°. There are a spread of Ba–Sb bond distances ranging from 3.64–4.10 Å. In the eighth Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to six Sb+2.78- atoms. There are a spread of Ba–Sb bond distances ranging from 3.42–4.09 Å. In the ninth Ba2+ site, Ba2+ is bonded to six Sb+2.78- atoms to form distorted BaSb6 octahedra that share corners with seven BaSb6 octahedra, corners with three BaSb7 pentagonal bipyramids, a cornercorner with one CdSb4 tetrahedra, edges with three BaSb6 octahedra, an edgeedge with one CdSb4 tetrahedra, faces with four BaSb6 octahedra, and a faceface with one BaSb7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 33–51°. There are a spread of Ba–Sb bond distances ranging from 3.45–3.73 Å. In the tenth Ba2+ site, Ba2+ is bonded to seven Sb+2.78- atoms to form BaSb7 pentagonal bipyramids that share corners with four BaSb6 octahedra, corners with four equivalent BaSb7 pentagonal bipyramids, a cornercorner with one CdSb4 tetrahedra, an edgeedge with one BaSb7 pentagonal bipyramid, an edgeedge with one CdSb4 tetrahedra, faces with four BaSb6 octahedra, faces with two equivalent BaSb7 pentagonal bipyramids, and faces with two equivalent CdSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 40–51°. There are a spread of Ba–Sb bond distances ranging from 3.64–4.09 Å. In the eleventh Ba2+ site, Ba2+ is bonded to seven Sb+2.78- atoms to form distorted BaSb7 pentagonal bipyramids that share corners with eight BaSb6 octahedra, corners with two equivalent BaSb7 pentagonal bipyramids, corners with four CdSb4 tetrahedra, faces with three BaSb6 octahedra, and faces with three BaSb7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 36–48°. There are a spread of Ba–Sb bond distances ranging from 3.48–4.12 Å. In the twelfth Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to six Sb+2.78- atoms. There are a spread of Ba–Sb bond distances ranging from 3.45–4.21 Å. There are three inequivalent Cd2+ sites. In the first Cd2+ site, Cd2+ is bonded to four Sb+2.78- atoms to form CdSb4 tetrahedra that share corners with six BaSb6 octahedra, corners with two equivalent BaSb7 pentagonal bipyramids, a cornercorner with one CdSb4 tetrahedra, edges with four BaSb6 octahedra, an edgeedge with one CdSb4 tetrahedra, and faces with two BaSb7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 35–54°. There are a spread of Cd–Sb bond distances ranging from 2.98–3.15 Å. In the second Cd2+ site, Cd2+ is bonded to four Sb+2.78- atoms to form CdSb4 tetrahedra that share corners with two equivalent BaSb6 octahedra, corners with three BaSb7 pentagonal bipyramids, corners with two equivalent CdSb4 tetrahedra, edges with two equivalent BaSb6 octahedra, an edgeedge with one BaSb7 pentagonal bipyramid, an edgeedge with one CdSb4 tetrahedra, and faces with two equivalent BaSb6 octahedra. The corner-sharing octahedral tilt angles are 44°. There are a spread of Cd–Sb bond distances ranging from 2.92–3.09 Å. In the third Cd2+ site, Cd2+ is bonded to four Sb+2.78- atoms to form CdSb4 tetrahedra that share corners with eight BaSb6 octahedra, corners with four BaSb7 pentagonal bipyramids, and an edgeedge with one CdSb4 tetrahedra. The corner-sharing octahedra tilt angles range from 39–60°. There are a spread of Cd–Sb bond distances ranging from 2.98–3.04 Å. There are fourteen inequivalent Sb+2.78- sites. In the first Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to six Ba2+ and two equivalent Cd2+ atoms. In the second Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to seven Ba2+ and one Cd2+ atom. In the third Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to eight Ba2+ and one Cd2+ atom. In the fourth Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to eight Ba2+ and one Cd2+ atom. In the fifth Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to eight Ba2+ and one Sb+2.78- atom. The Sb–Sb bond length is 2.95 Å. In the sixth Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to eight Ba2+ atoms. In the seventh Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to eight Ba2+ and one Cd2+ atom. In the eighth Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to six Ba2+ and two Cd2+ atoms. In the ninth Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to eight Ba2+ atoms. In the tenth Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to eight Ba2+ and one Sb+2.78- atom. The Sb–Sb bond length is 2.95 Å. In the eleventh Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to eight Ba2+ atoms. In the twelfth Sb+2.78- site, Sb+2.78- is bonded in a 8-coordinate geometry to seven Ba2+ and one Sb+2.78- atom. The Sb–Sb bond length is 2.86 Å. In the thirteenth Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to six Ba2+ and three Cd2+ atoms. In the fourteenth Sb+2.78- site, Sb+2.78- is bonded in a 9-coordinate geometry to seven Ba2+, one Cd2+, and one Sb+2.78- atom.