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DOE OSTI · 1695889

Materials Data on Y4CdS7 by Materials Project

Abstract

Y4CdS7 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are four inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded to seven S2- atoms to form distorted YS7 pentagonal bipyramids that share corners with four YS6 octahedra, corners with four equivalent CdS6 octahedra, an edgeedge with one CdS6 octahedra, edges with three equivalent YS6 octahedra, edges with two equivalent YS7 pentagonal bipyramids, and faces with two equivalent YS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 22–70°. There are a spread of Y–S bond distances ranging from 2.72–3.06 Å. In the second Y3+ site, Y3+ is bonded to seven S2- atoms to form distorted YS7 pentagonal bipyramids that share corners with two equivalent CdS6 octahedra, corners with six YS6 octahedra, edges with four YS6 octahedra, edges with two equivalent YS7 pentagonal bipyramids, and faces with two equivalent YS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 21–69°. There are a spread of Y–S bond distances ranging from 2.71–3.00 Å. In the third Y3+ site, Y3+ is bonded to six S2- atoms to form YS6 octahedra that share a cornercorner with one YS6 octahedra, a cornercorner with one CdS6 octahedra, corners with four YS7 pentagonal bipyramids, edges with two equivalent YS6 octahedra, and edges with six YS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 54–56°. There are a spread of Y–S bond distances ranging from 2.67–2.75 Å. In the fourth Y3+ site, Y3+ is bonded to six S2- atoms to form YS6 octahedra that share a cornercorner with one YS6 octahedra, corners with two equivalent CdS6 octahedra, corners with six YS7 pentagonal bipyramids, edges with two equivalent YS6 octahedra, edges with three equivalent CdS6 octahedra, and an edgeedge with one YS7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 3–54°. There are a spread of Y–S bond distances ranging from 2.67–2.80 Å. Cd2+ is bonded to six S2- atoms to form CdS6 octahedra that share corners with three YS6 octahedra, corners with six YS7 pentagonal bipyramids, edges with two equivalent CdS6 octahedra, edges with three equivalent YS6 octahedra, and an edgeedge with one YS7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 3–56°. There are a spread of Cd–S bond distances ranging from 2.65–2.79 Å. There are seven inequivalent S2- sites. In the first S2- site, S2- is bonded to four Y3+ and one Cd2+ atom to form distorted SY4Cd trigonal bipyramids that share corners with five SY3Cd tetrahedra, corners with four SY5 trigonal bipyramids, an edgeedge with one SY4 tetrahedra, and edges with five SY4Cd trigonal bipyramids. In the second S2- site, S2- is bonded to three Y3+ and two equivalent Cd2+ atoms to form distorted SY3Cd2 trigonal bipyramids that share corners with five SY3Cd tetrahedra, corners with four SY5 trigonal bipyramids, an edgeedge with one SY3Cd tetrahedra, and edges with five SY4Cd trigonal bipyramids. In the third S2- site, S2- is bonded to five Y3+ atoms to form distorted SY5 trigonal bipyramids that share corners with four equivalent SY3Cd tetrahedra, corners with six SY4Cd trigonal bipyramids, edges with three SY3Cd tetrahedra, and edges with six SY3Cd2 trigonal bipyramids. In the fourth S2- site, S2- is bonded to five Y3+ atoms to form distorted SY5 trigonal bipyramids that share corners with four equivalent SY4 tetrahedra, corners with six SY4Cd trigonal bipyramids, edges with three SY3Cd tetrahedra, and edges with six SY4Cd trigonal bipyramids. In the fifth S2- site, S2- is bonded to three Y3+ and one Cd2+ atom to form distorted SY3Cd tetrahedra that share corners with three SY3Cd tetrahedra, corners with nine SY4Cd trigonal bipyramids, and edges with four SY3Cd2 trigonal bipyramids. In the sixth S2- site, S2- is bonded to four Y3+ atoms to form distorted SY4 tetrahedra that share corners with three SY3Cd tetrahedra, corners with nine SY4Cd trigonal bipyramids, and edges with four SY4Cd trigonal bipyramids. In the seventh S2- site, S2- is bonded in a rectangular see-saw-like geometry to two equivalent Y3+ and two equivalent Cd2+ atoms.

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2020-05-02. Materials Data on Y4CdS7 by Materials Project. https://doi.org/10.17188/1695889

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