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DOE OSTI · 1758589

Materials Data on Ba4Ga5AgSe12 by Materials Project

Abstract

Ba4AgGa5Se12 crystallizes in the tetragonal P-4 space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to one Ag1+ and eight Se2- atoms. The Ba–Ag bond length is 3.43 Å. There are a spread of Ba–Se bond distances ranging from 3.36–3.79 Å. In the second Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to one Ag1+ and eight Se2- atoms. The Ba–Ag bond length is 3.42 Å. There are a spread of Ba–Se bond distances ranging from 3.37–3.78 Å. Ag1+ is bonded to four Ba2+ and four Se2- atoms to form distorted AgBa4Se4 tetrahedra that share corners with four GaSe4 tetrahedra. All Ag–Se bond lengths are 2.65 Å. There are four inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to four Se2- atoms to form GaSe4 tetrahedra that share a cornercorner with one AgBa4Se4 tetrahedra and corners with three GaSe4 tetrahedra. There are a spread of Ga–Se bond distances ranging from 2.42–2.46 Å. In the second Ga3+ site, Ga3+ is bonded to four Se2- atoms to form GaSe4 tetrahedra that share a cornercorner with one AgBa4Se4 tetrahedra and corners with three GaSe4 tetrahedra. There are a spread of Ga–Se bond distances ranging from 2.42–2.47 Å. In the third Ga3+ site, Ga3+ is bonded to four equivalent Se2- atoms to form corner-sharing GaSe4 tetrahedra. All Ga–Se bond lengths are 2.45 Å. In the fourth Ga3+ site, Ga3+ is bonded to four equivalent Se2- atoms to form corner-sharing GaSe4 tetrahedra. All Ga–Se bond lengths are 2.45 Å. There are six inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 2-coordinate geometry to two equivalent Ba2+ and two Ga3+ atoms. In the second Se2- site, Se2- is bonded in a 2-coordinate geometry to two equivalent Ba2+ and two Ga3+ atoms. In the third Se2- site, Se2- is bonded in a 4-coordinate geometry to two equivalent Ba2+ and two Ga3+ atoms. In the fourth Se2- site, Se2- is bonded in a 4-coordinate geometry to two equivalent Ba2+ and two Ga3+ atoms. In the fifth Se2- site, Se2- is bonded in a 2-coordinate geometry to four Ba2+, one Ag1+, and one Ga3+ atom. In the sixth Se2- site, Se2- is bonded in a 2-coordinate geometry to four Ba2+, one Ag1+, and one Ga3+ atom.

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2020-09-03. Materials Data on Ba4Ga5AgSe12 by Materials Project. https://doi.org/10.17188/1758589

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