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DOE OSTI · 1718426

Materials Data on Ba2GaS4 by Materials Project

Abstract

Ba2GaS4 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are four inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded to seven S+1.75- atoms to form distorted BaS7 pentagonal bipyramids that share a cornercorner with one BaS8 hexagonal bipyramid, corners with two equivalent BaS7 pentagonal bipyramids, corners with three GaS4 tetrahedra, an edgeedge with one BaS8 hexagonal bipyramid, edges with two equivalent BaS7 pentagonal bipyramids, and edges with two equivalent GaS4 tetrahedra. There are a spread of Ba–S bond distances ranging from 3.17–3.41 Å. In the second Ba2+ site, Ba2+ is bonded in a 8-coordinate geometry to eight S+1.75- atoms. There are a spread of Ba–S bond distances ranging from 3.21–3.58 Å. In the third Ba2+ site, Ba2+ is bonded to eight S+1.75- atoms to form distorted BaS8 hexagonal bipyramids that share corners with two equivalent BaS8 hexagonal bipyramids, a cornercorner with one BaS7 pentagonal bipyramid, a cornercorner with one GaS4 tetrahedra, edges with two equivalent BaS8 hexagonal bipyramids, an edgeedge with one BaS7 pentagonal bipyramid, and edges with three GaS4 tetrahedra. There are a spread of Ba–S bond distances ranging from 3.13–3.38 Å. In the fourth Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to nine S+1.75- atoms. There are a spread of Ba–S bond distances ranging from 3.18–3.60 Å. There are two inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to four S+1.75- atoms to form GaS4 tetrahedra that share a cornercorner with one BaS7 pentagonal bipyramid, corners with two equivalent GaS4 tetrahedra, an edgeedge with one BaS8 hexagonal bipyramid, and edges with two equivalent BaS7 pentagonal bipyramids. There are a spread of Ga–S bond distances ranging from 2.26–2.34 Å. In the second Ga3+ site, Ga3+ is bonded to four S+1.75- atoms to form GaS4 tetrahedra that share a cornercorner with one BaS8 hexagonal bipyramid, corners with two equivalent BaS7 pentagonal bipyramids, corners with two equivalent GaS4 tetrahedra, and edges with two equivalent BaS8 hexagonal bipyramids. There are a spread of Ga–S bond distances ranging from 2.25–2.37 Å. There are eight inequivalent S+1.75- sites. In the first S+1.75- site, S+1.75- is bonded to four Ba2+ and one Ga3+ atom to form distorted SBa4Ga trigonal bipyramids that share a cornercorner with one SBa5Ga octahedra, corners with two equivalent SBa4Ga trigonal bipyramids, corners with three equivalent SBa2Ga2 trigonal pyramids, edges with two equivalent SBa4Ga trigonal bipyramids, and an edgeedge with one SBa2Ga2 trigonal pyramid. The corner-sharing octahedral tilt angles are 39°. In the second S+1.75- site, S+1.75- is bonded in a 5-coordinate geometry to four Ba2+ and one Ga3+ atom. In the third S+1.75- site, S+1.75- is bonded to two Ba2+ and two Ga3+ atoms to form distorted SBa2Ga2 trigonal pyramids that share corners with three equivalent SBa4Ga trigonal bipyramids, an edgeedge with one SBa5Ga octahedra, and an edgeedge with one SBa4Ga trigonal bipyramid. In the fourth S+1.75- site, S+1.75- is bonded in a 5-coordinate geometry to three Ba2+ and two Ga3+ atoms. In the fifth S+1.75- site, S+1.75- is bonded in a 1-coordinate geometry to four Ba2+ and one Ga3+ atom. In the sixth S+1.75- site, S+1.75- is bonded to five Ba2+ and one Ga3+ atom to form distorted SBa5Ga octahedra that share corners with two equivalent SBa5Ga octahedra, a cornercorner with one SBa4Ga trigonal bipyramid, edges with two equivalent SBa5Ga octahedra, and an edgeedge with one SBa2Ga2 trigonal pyramid. The corner-sharing octahedral tilt angles are 17°. In the seventh S+1.75- site, S+1.75- is bonded in a 6-coordinate geometry to five Ba2+ and one S+1.75- atom. The S–S bond length is 2.11 Å. In the eighth S+1.75- site, S+1.75- is bonded in a 6-coordinate geometry to five Ba2+ and one S+1.75- atom.

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2020-04-30. Materials Data on Ba2GaS4 by Materials Project. https://doi.org/10.17188/1718426

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