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DOE OSTI · 1683432

Materials Data on Ba9U4(Ag5S12)2 by Materials Project

Abstract

Ba9Ag10U4S24 crystallizes in the tetragonal I4cm space group. The structure is three-dimensional. there are three 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 3.15–3.36 Å. In the second 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 3.25–3.35 Å. In the third Ba2+ site, Ba2+ is bonded in a distorted q6 geometry to ten S2- atoms. There are a spread of Ba–S bond distances ranging from 3.40–3.54 Å. There are three inequivalent U5+ sites. In the first U5+ site, U5+ is bonded to six S2- atoms to form US6 octahedra that share a cornercorner with one AgS4 trigonal pyramid and edges with four equivalent AgS4 tetrahedra. There are a spread of U–S bond distances ranging from 2.58–2.78 Å. In the second U5+ site, U5+ is bonded to six S2- atoms to form US6 octahedra that share edges with two equivalent AgS4 tetrahedra and an edgeedge with one AgS4 trigonal pyramid. There are a spread of U–S bond distances ranging from 2.61–2.65 Å. In the third U5+ site, U5+ is bonded to six S2- atoms to form US6 octahedra that share corners with four equivalent AgS4 tetrahedra. There are a spread of U–S bond distances ranging from 2.56–2.64 Å. There are five inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded to four S2- atoms to form AgS4 tetrahedra that share corners with two equivalent AgS4 tetrahedra, a cornercorner with one AgS4 trigonal pyramid, and edges with two equivalent US6 octahedra. There are a spread of Ag–S bond distances ranging from 2.56–2.71 Å. In the second Ag1+ site, Ag1+ is bonded to four S2- atoms to form distorted AgS4 tetrahedra that share corners with two equivalent US6 octahedra, a cornercorner with one AgS4 trigonal pyramid, and an edgeedge with one US6 octahedra. The corner-sharing octahedral tilt angles are 9°. There are a spread of Ag–S bond distances ranging from 2.57–2.63 Å. In the third Ag1+ site, Ag1+ is bonded in a trigonal planar geometry to three S2- atoms. There are one shorter (2.40 Å) and two longer (2.45 Å) Ag–S bond lengths. In the fourth Ag1+ site, Ag1+ is bonded to four S2- atoms to form AgS4 trigonal pyramids that share corners with two equivalent US6 octahedra, corners with six AgS4 tetrahedra, and an edgeedge with one US6 octahedra. The corner-sharing octahedral tilt angles are 13°. There are two shorter (2.63 Å) and two longer (2.79 Å) Ag–S bond lengths. In the fifth Ag1+ site, Ag1+ is bonded in a distorted square co-planar geometry to four S2- atoms. There are two shorter (2.57 Å) and two longer (2.90 Å) Ag–S bond lengths. There are ten inequivalent S2- sites. In the first S2- site, S2- is bonded to four Ba2+ and one U5+ atom to form distorted SBa4U square pyramids that share corners with two equivalent SBa5U octahedra, a cornercorner with one SBa4U square pyramid, edges with eight SBa2UAg3 octahedra, and edges with two equivalent SBa2UAg2 square pyramids. The corner-sharing octahedral tilt angles are 44°. In the second S2- site, S2- is bonded to two equivalent Ba2+, one U5+, and three Ag1+ atoms to form SBa2UAg3 octahedra that share corners with ten SBa2UAg3 octahedra and edges with three SBa2UAg2 square pyramids. The corner-sharing octahedra tilt angles range from 3–52°. In the third S2- site, S2- is bonded to five Ba2+ and one U5+ atom to form distorted SBa5U octahedra that share corners with four equivalent SBa2UAg3 octahedra, corners with eight SBa4U square pyramids, and faces with four equivalent SBa4UAg octahedra. The corner-sharing octahedral tilt angles are 52°. In the fourth S2- site, S2- is bonded in a 1-coordinate geometry to five Ba2+ and one U5+ atom. In the fifth S2- site, S2- is bonded in a 6-coordinate geometry to three Ba2+, one U5+, and two Ag1+ atoms. In the sixth S2- site, S2- is bonded to four Ba2+, one U5+, and one Ag1+ atom to form distorted SBa4UAg octahedra that share corners with seven SBa4UAg octahedra, a cornercorner with one SBa2UAg2 square pyramid, an edgeedge with one SBa2UAg3 octahedra, edges with three SBa4U square pyramids, and faces with three SBa5U octahedra. The corner-sharing octahedra tilt angles range from 0–51°. In the seventh S2- site, S2- is bonded in a 5-coordinate geometry to three Ba2+, one U5+, and one Ag1+ atom. In the eighth S2- site, S2- is bonded to two equivalent Ba2+, one U5+, and two Ag1+ atoms to form distorted SBa2UAg2 square pyramids that share corners with five SBa4UAg octahedra, edges with five SBa4UAg octahedra, and edges with three SBa4U square pyramids. The corner-sharing octahedra tilt angles range from 7–51°. In the ninth S2- site, S2- is bonded to two equivalent Ba2+, one U5+, and three Ag1+ atoms to form distorted SBa2UAg3 octahedra that share corners with eight SBa2UAg3 octahedra, edges with two equivalent SBa2UAg3 octahedra, and an edgeedge with one SBa4U square pyramid. The corner-sharing octahedra tilt angles range from 3–52°. In the tenth S2- site, S2- is bonded to two equivalent Ba2+, one U5+, and three Ag1+ atoms to form distorted SBa2UAg3 octahedra that share corners with two equivalent SBa4UAg octahedra, a cornercorner with one SBa2UAg2 square pyramid, edges with five SBa4UAg octahedra, and edges with three SBa4U square pyramids. The corner-sharing octahedral tilt angles are 51°.

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2020-06-05. Materials Data on Ba9U4(Ag5S12)2 by Materials Project. https://doi.org/10.17188/1683432

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