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DOE OSTI · 1276527

Materials Data on Cs3As11 by Materials Project

Abstract

Cs3As11 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are three inequivalent Cs1+ sites. In the first Cs1+ site, Cs1+ is bonded in a 10-coordinate geometry to ten As+0.27- atoms. There are a spread of Cs–As bond distances ranging from 3.85–4.27 Å. In the second Cs1+ site, Cs1+ is bonded in a 10-coordinate geometry to ten As+0.27- atoms. There are a spread of Cs–As bond distances ranging from 3.77–4.12 Å. In the third Cs1+ site, Cs1+ is bonded in a 8-coordinate geometry to eight As+0.27- atoms. There are a spread of Cs–As bond distances ranging from 3.71–4.07 Å. There are eleven inequivalent As+0.27- sites. In the first As+0.27- site, As+0.27- is bonded to two Cs1+ and three As+0.27- atoms to form distorted AsCs2As3 square pyramids that share corners with two equivalent AsCs3As3 octahedra, corners with six AsCs3As2 trigonal bipyramids, corners with two equivalent AsCsAs3 trigonal pyramids, and an edgeedge with one AsCs3As2 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 35–80°. There are a spread of As–As bond distances ranging from 2.50–2.52 Å. In the second As+0.27- site, As+0.27- is bonded in a 6-coordinate geometry to three Cs1+ and three As+0.27- atoms. There are one shorter (2.43 Å) and one longer (2.48 Å) As–As bond lengths. In the third As+0.27- site, As+0.27- is bonded in a 6-coordinate geometry to three Cs1+ and three As+0.27- atoms. All As–As bond lengths are 2.51 Å. In the fourth As+0.27- site, As+0.27- is bonded to one Cs1+ and three As+0.27- atoms to form AsCsAs3 trigonal pyramids that share a cornercorner with one AsCs3As3 octahedra, corners with two equivalent AsCs2As3 square pyramids, and corners with four AsCs3As2 trigonal bipyramids. The corner-sharing octahedral tilt angles are 78°. There are one shorter (2.42 Å) and one longer (2.48 Å) As–As bond lengths. In the fifth As+0.27- site, As+0.27- is bonded to three Cs1+ and two As+0.27- atoms to form distorted AsCs3As2 trigonal bipyramids that share corners with four equivalent AsCs3As3 octahedra, a cornercorner with one AsCs2As3 square pyramid, corners with two AsCs2As3 trigonal bipyramids, a cornercorner with one AsCsAs3 trigonal pyramid, an edgeedge with one AsCs2As3 square pyramid, and edges with two AsCs3As2 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 22–59°. There are one shorter (2.42 Å) and one longer (2.43 Å) As–As bond lengths. In the sixth As+0.27- site, As+0.27- is bonded in a distorted rectangular see-saw-like geometry to two Cs1+ and three As+0.27- atoms. In the seventh As+0.27- site, As+0.27- is bonded to three Cs1+ and three As+0.27- atoms to form distorted AsCs3As3 octahedra that share corners with two equivalent AsCs2As3 square pyramids, corners with nine AsCs3As2 trigonal bipyramids, a cornercorner with one AsCsAs3 trigonal pyramid, an edgeedge with one AsCs3As3 octahedra, and an edgeedge with one AsCs3As2 trigonal bipyramid. There are one shorter (2.43 Å) and one longer (2.48 Å) As–As bond lengths. In the eighth As+0.27- site, As+0.27- is bonded to two Cs1+ and three As+0.27- atoms to form distorted AsCs2As3 trigonal bipyramids that share corners with three equivalent AsCs3As3 octahedra, corners with two equivalent AsCs2As3 square pyramids, corners with three AsCs3As2 trigonal bipyramids, and corners with two equivalent AsCsAs3 trigonal pyramids. The corner-sharing octahedra tilt angles range from 21–79°. In the ninth As+0.27- site, As+0.27- is bonded to three Cs1+ and two As+0.27- atoms to form AsCs3As2 trigonal bipyramids that share corners with two equivalent AsCs3As3 octahedra, corners with three equivalent AsCs2As3 square pyramids, corners with three AsCs3As2 trigonal bipyramids, a cornercorner with one AsCsAs3 trigonal pyramid, an edgeedge with one AsCs3As3 octahedra, and an edgeedge with one AsCs3As2 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 55–88°. The As–As bond length is 2.42 Å. In the tenth As+0.27- site, As+0.27- is bonded in a 6-coordinate geometry to four Cs1+ and two As+0.27- atoms. In the eleventh As+0.27- site, As+0.27- is bonded in a 5-coordinate geometry to two Cs1+ and three As+0.27- atoms.

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2020-04-29. Materials Data on Cs3As11 by Materials Project. https://doi.org/10.17188/1276527

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