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DOE OSTI · 1697215

Materials Data on TmAgS2 by Materials Project

Abstract

TmAgS2 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are four inequivalent Tm3+ sites. In the first Tm3+ site, Tm3+ is bonded to six S2- atoms to form TmS6 octahedra that share corners with four equivalent TmS6 octahedra, a cornercorner with one AgS5 trigonal bipyramid, edges with four TmS6 octahedra, and edges with four AgS5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 15–20°. There are a spread of Tm–S bond distances ranging from 2.71–2.74 Å. In the second Tm3+ site, Tm3+ is bonded to six S2- atoms to form TmS6 octahedra that share corners with four equivalent TmS6 octahedra, corners with two equivalent AgS5 trigonal bipyramids, edges with four TmS6 octahedra, and edges with two equivalent AgS5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 15–20°. There are a spread of Tm–S bond distances ranging from 2.70–2.74 Å. In the third Tm3+ site, Tm3+ is bonded to six S2- atoms to form TmS6 octahedra that share corners with four equivalent TmS6 octahedra, a cornercorner with one AgS5 trigonal bipyramid, edges with four TmS6 octahedra, and edges with four AgS5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 15–20°. There are a spread of Tm–S bond distances ranging from 2.70–2.74 Å. In the fourth Tm3+ site, Tm3+ is bonded to six S2- atoms to form TmS6 octahedra that share corners with four equivalent TmS6 octahedra, corners with two equivalent AgS5 trigonal bipyramids, edges with four TmS6 octahedra, and edges with two equivalent AgS5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 15–20°. There are a spread of Tm–S bond distances ranging from 2.71–2.73 Å. There are four inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded to five S2- atoms to form distorted AgS5 trigonal bipyramids that share corners with three TmS6 octahedra, corners with four equivalent AgS5 trigonal bipyramids, and edges with six TmS6 octahedra. The corner-sharing octahedra tilt angles range from 7–79°. There are a spread of Ag–S bond distances ranging from 2.49–3.10 Å. In the second Ag1+ site, Ag1+ is bonded in a 6-coordinate geometry to five S2- atoms. There are a spread of Ag–S bond distances ranging from 2.49–3.24 Å. In the third Ag1+ site, Ag1+ is bonded to five S2- atoms to form AgS5 trigonal bipyramids that share corners with three TmS6 octahedra, corners with four equivalent AgS5 trigonal bipyramids, and edges with six TmS6 octahedra. The corner-sharing octahedra tilt angles range from 8–76°. There are a spread of Ag–S bond distances ranging from 2.49–3.03 Å. In the fourth Ag1+ site, Ag1+ is bonded in a 6-coordinate geometry to six S2- atoms. There are a spread of Ag–S bond distances ranging from 2.51–3.64 Å. There are eight inequivalent S2- sites. In the first S2- site, S2- is bonded to three Tm3+ and two Ag1+ atoms to form distorted STm3Ag2 square pyramids that share corners with two equivalent STm3Ag3 octahedra, corners with two STm3Ag2 square pyramids, edges with two equivalent STm3Ag3 octahedra, and an edgeedge with one STm3Ag2 square pyramid. The corner-sharing octahedra tilt angles range from 79–81°. In the second S2- site, S2- is bonded to three Tm3+ and three Ag1+ atoms to form distorted STm3Ag3 octahedra that share corners with five STm3Ag2 square pyramids, edges with two equivalent STm3Ag3 octahedra, and edges with four STm3Ag2 square pyramids. In the third S2- site, S2- is bonded to three Tm3+ and three Ag1+ atoms to form distorted STm3Ag3 octahedra that share corners with seven STm3Ag2 square pyramids, edges with two equivalent STm3Ag3 octahedra, and edges with two equivalent STm3Ag2 square pyramids. In the fourth S2- site, S2- is bonded in a 6-coordinate geometry to three Tm3+ and three Ag1+ atoms. In the fifth S2- site, S2- is bonded to three Tm3+ and two equivalent Ag1+ atoms to form STm3Ag2 square pyramids that share corners with five STm3Ag3 octahedra, a cornercorner with one STm3Ag2 square pyramid, edges with two equivalent STm3Ag3 octahedra, and edges with two equivalent STm3Ag2 square pyramids. The corner-sharing octahedra tilt angles range from 4–25°. In the sixth S2- site, S2- is bonded in a 5-coordinate geometry to three Tm3+ and three Ag1+ atoms. In the seventh S2- site, S2- is bonded to three Tm3+ and two equivalent Ag1+ atoms to form STm3Ag2 square pyramids that share corners with five STm3Ag3 octahedra, a cornercorner with one STm3Ag2 square pyramid, edges with two equivalent STm3Ag3 octahedra, and edges with three STm3Ag2 square pyramids. The corner-sharing octahedra tilt angles range from 4–23°. In the eighth S2- site, S2- is bonded in a 6-coordinate geometry to three Tm3+ and three Ag1+ atoms.

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2020-04-29. Materials Data on TmAgS2 by Materials Project. https://doi.org/10.17188/1697215

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