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DOE OSTI · 1267619

Materials Data on Ba2LaAg5S6 by Materials Project

Abstract

Ba2LaAg5S6 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Ba2+ is bonded to seven S2- atoms to form distorted BaS7 pentagonal bipyramids that share corners with two equivalent LaS6 octahedra, corners with three equivalent AgS4 tetrahedra, corners with two equivalent AgS4 trigonal pyramids, edges with three equivalent LaS6 octahedra, edges with two equivalent BaS7 pentagonal bipyramids, edges with three equivalent AgS4 tetrahedra, edges with three equivalent AgS4 trigonal pyramids, 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 3.22–3.32 Å. La3+ is bonded to six S2- atoms to form LaS6 octahedra that share corners with four equivalent BaS7 pentagonal bipyramids, corners with two equivalent AgS4 trigonal pyramids, edges with two equivalent LaS6 octahedra, edges with six equivalent BaS7 pentagonal bipyramids, and edges with four equivalent AgS4 tetrahedra. There are two shorter (2.90 Å) and four longer (2.93 Å) La–S bond lengths. There are three inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded to four S2- atoms to form distorted AgS4 trigonal pyramids that share a cornercorner with one LaS6 octahedra, corners with two equivalent BaS7 pentagonal bipyramids, corners with five equivalent AgS4 tetrahedra, corners with two equivalent AgS4 trigonal pyramids, edges with three equivalent BaS7 pentagonal bipyramids, and edges with two equivalent AgS4 trigonal pyramids. The corner-sharing octahedral tilt angles are 5°. There are a spread of Ag–S bond distances ranging from 2.60–2.91 Å. In the second Ag1+ site, Ag1+ is bonded to four S2- atoms to form distorted AgS4 tetrahedra that share corners with three equivalent BaS7 pentagonal bipyramids, corners with two equivalent AgS4 tetrahedra, corners with five equivalent AgS4 trigonal pyramids, edges with two equivalent LaS6 octahedra, and edges with three equivalent BaS7 pentagonal bipyramids. There are a spread of Ag–S bond distances ranging from 2.59–2.74 Å. In the third Ag1+ site, Ag1+ is bonded in a linear geometry to two equivalent S2- atoms. Both Ag–S bond lengths are 2.41 Å. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded to two equivalent Ba2+, one La3+, and three Ag1+ atoms to form a mixture of edge and corner-sharing SBa2LaAg3 octahedra. The corner-sharing octahedra tilt angles range from 0–26°. In the second S2- site, S2- is bonded in a 7-coordinate geometry to two equivalent Ba2+ and five Ag1+ atoms. In the third S2- site, S2- is bonded to three equivalent Ba2+, two equivalent La3+, and one Ag1+ atom to form a mixture of distorted edge and corner-sharing SBa3La2Ag octahedra. The corner-sharing octahedra tilt angles range from 0–26°.

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2020-07-15. Materials Data on Ba2LaAg5S6 by Materials Project. https://doi.org/10.17188/1267619

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36 MATERIALS SCIENCE↗