DOE OSTI2020
Ba4Tb2Cd3S10 crystallizes in the orthorhombic Cmc2_1 space group. The structure is three-dimensional. there are four inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Ba–S bond distances ranging from 3.16–3.76 Å. In the second Ba2+ site, Ba2+ is bonded to seven S2- atoms to form distorted BaS7 pentagonal bipyramids that share corners with two equivalent TbS6 octahedra, corners with two equivalent BaS7 pentagonal bipyramids, edges with three TbS6 octahedra, edges with three equivalent BaS7 pentagonal bipyramids, edges with two equivalent CdS4 tetrahedra, edges with two equivalent CdS4 trigonal pyramids, and faces with two equivalent BaS7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 16°. There are a spread of Ba–S bond distances ranging from 3.11–3.33 Å. In the third Ba2+ site, Ba2+ is bonded to seven S2- atoms to form distorted BaS7 pentagonal bipyramids that share corners with two equivalent TbS6 octahedra, corners with two equivalent BaS7 pentagonal bipyramids, corners with two equivalent CdS4 tetrahedra, corners with five CdS4 trigonal pyramids, edges with three TbS6 octahedra, edges with three equivalent BaS7 pentagonal bipyramids, an edgeedge with one CdS4 trigonal pyramid, and faces with two equivalent BaS7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 21°. There are a spread of Ba–S bond distances ranging from 3.17–3.36 Å. In the fourth Ba2+ site, Ba2+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Ba–S bond distances ranging from 3.14–3.57 Å. There are two inequivalent Tb3+ sites. In the first Tb3+ site, Tb3+ is bonded to six S2- atoms to form TbS6 octahedra that share corners with two equivalent BaS7 pentagonal bipyramids, edges with two equivalent TbS6 octahedra, edges with three BaS7 pentagonal bipyramids, and edges with four CdS4 trigonal pyramids. There are a spread of Tb–S bond distances ranging from 2.77–2.84 Å. In the second Tb3+ site, Tb3+ is bonded to six S2- atoms to form TbS6 octahedra that share corners with two equivalent BaS7 pentagonal bipyramids, corners with three equivalent CdS4 tetrahedra, edges with two equivalent TbS6 octahedra, and edges with three BaS7 pentagonal bipyramids. There are a spread of Tb–S bond distances ranging from 2.77–2.81 Å. There are three inequivalent Cd2+ sites. In the first Cd2+ site, Cd2+ is bonded to four S2- atoms to form CdS4 tetrahedra that share corners with three equivalent TbS6 octahedra, corners with two equivalent BaS7 pentagonal bipyramids, corners with two equivalent CdS4 tetrahedra, a cornercorner with one CdS4 trigonal pyramid, and edges with two equivalent BaS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 6–70°. There are a spread of Cd–S bond distances ranging from 2.48–2.72 Å. In the second Cd2+ site, Cd2+ is bonded to four S2- atoms to form distorted CdS4 trigonal pyramids that share corners with two equivalent BaS7 pentagonal bipyramids, corners with two equivalent CdS4 trigonal pyramids, edges with two equivalent TbS6 octahedra, and an edgeedge with one BaS7 pentagonal bipyramid. There are a spread of Cd–S bond distances ranging from 2.46–2.73 Å. In the third Cd2+ site, Cd2+ is bonded to four S2- atoms to form CdS4 trigonal pyramids that share corners with three equivalent BaS7 pentagonal bipyramids, a cornercorner with one CdS4 tetrahedra, corners with two equivalent CdS4 trigonal pyramids, edges with two equivalent TbS6 octahedra, and edges with two equivalent BaS7 pentagonal bipyramids. There are a spread of Cd–S bond distances ranging from 2.55–2.70 Å. There are ten inequivalent S2- sites. In the first S2- site, S2- is bonded to three Ba2+ and two equivalent Tb3+ atoms to form distorted SBa3Tb2 trigonal bipyramids that share corners with six SBa4Cd square pyramids, edges with two equivalent SBa4TbCd octahedra, edges with two SBa3Tb2 square pyramids, and edges with two equivalent SBa3Tb2 trigonal bipyramids. In the second S2- site, S2- is bonded to three Ba2+ and two equivalent Tb3+ atoms to form distorted SBa3Tb2 square pyramids that share corners with four equivalent SBa4Cd2 octahedra, corners with two equivalent SBa2TbCd2 square pyramids, corners with two equivalent SBa3Tb2 trigonal bipyramids, edges with five SBa4Cd2 octahedra, edges with three SBa3Tb2 square pyramids, and an edgeedge with one SBa3Tb2 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 40–50°. In the third S2- site, S2- is bonded in a 5-coordinate geometry to two equivalent Ba2+, one Tb3+, and two equivalent Cd2+ atoms. In the fourth S2- site, S2- is bonded to two equivalent Ba2+, one Tb3+, and two equivalent Cd2+ atoms to form distorted SBa2TbCd2 square pyramids that share corners with two equivalent SBa4Cd2 octahedra, corners with four SBa3Tb2 square pyramids, edges with three SBa4Cd2 octahedra, and edges with three SBa3Tb2 square pyramids. The corner-sharing octahedral tilt angles are 54°. In the fifth S2- site, S2- is bonded in a distorted trigonal non-coplanar geometry to two Ba2+, one Tb3+, and two equivalent Cd2+ atoms. In the sixth S2- site, S2- is bonded to four Ba2+ and one Cd2+ atom to form distorted SBa4Cd square pyramids that share corners with two equivalent SBa4TbCd octahedra, corners with two equivalent SBa2TbCd2 square pyramids, corners with four equivalent SBa3Tb2 trigonal bipyramids, an edgeedge with one SBa4TbCd octahedra, edges with two equivalent SBa4Cd square pyramids, and an edgeedge with one SBa3Tb2 trigonal bipyramid. The corner-sharing octahedral tilt angles are 41°. In the seventh S2- site, S2- is bonded to four Ba2+ and two Cd2+ atoms to form distorted SBa4Cd2 octahedra that share corners with six SBa4TbCd octahedra, corners with six SBa3Tb2 square pyramids, edges with two equivalent SBa4Cd2 octahedra, edges with two SBa2TbCd2 square pyramids, and faces with two SBa4TbCd octahedra. The corner-sharing octahedra tilt angles range from 41–59°. In the eighth S2- site, S2- is bonded to four Ba2+, one Tb3+, and one Cd2+ atom to form SBa4TbCd octahedra that share corners with four SBa4Cd2 octahedra, corners with two equivalent SBa4Cd square pyramids, edges with three SBa4TbCd octahedra, edges with three SBa3Tb2 square pyramids, edges with two equivalent SBa3Tb2 trigonal bipyramids, and a faceface with one SBa4Cd2 octahedra. The corner-sharing octahedra tilt angles range from 21–54°. In the ninth S2- site, S2- is bonded in a 6-coordinate geometry to three Ba2+, two equivalent Tb3+, and one Cd2+ atom. In the tenth S2- site, S2- is bonded to three Ba2+, two equivalent Tb3+, and one Cd2+ atom to form distorted SBa3Tb2Cd octahedra that share corners with six SBa4Cd2 octahedra, edges with three SBa4TbCd octahedra, edges with four SBa3Tb2 square pyramids, and a faceface with one SBa4Cd2 octahedra. The corner-sharing octahedra tilt angles range from 21–59°.