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DOE OSTI · 1741296

Materials Data on CeY4S7 by Materials Project

Abstract

CeY4S7 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. Ce is bonded to six S atoms to form CeS6 octahedra that share corners with three YS6 octahedra, corners with six YS7 pentagonal bipyramids, edges with two equivalent CeS6 octahedra, edges with three equivalent YS6 octahedra, and an edgeedge with one YS7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 2–58°. There are a spread of Ce–S bond distances ranging from 2.76–2.92 Å. There are four inequivalent Y sites. In the first Y site, Y is bonded to seven S atoms to form distorted YS7 pentagonal bipyramids that share corners with four equivalent CeS6 octahedra, corners with four YS6 octahedra, an edgeedge with one CeS6 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 21–65°. There are a spread of Y–S bond distances ranging from 2.75–2.98 Å. In the second Y site, Y is bonded to seven S atoms to form distorted YS7 pentagonal bipyramids that share corners with two equivalent CeS6 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 22–68°. There are a spread of Y–S bond distances ranging from 2.76–2.99 Å. In the third Y site, Y is bonded to six S atoms to form YS6 octahedra that share a cornercorner with one YS6 octahedra, corners with two equivalent CeS6 octahedra, corners with six YS7 pentagonal bipyramids, edges with two equivalent YS6 octahedra, edges with three equivalent CeS6 octahedra, and an edgeedge with one YS7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 2–58°. There are a spread of Y–S bond distances ranging from 2.68–2.86 Å. In the fourth Y site, Y is bonded to six S atoms to form YS6 octahedra that share a cornercorner with one CeS6 octahedra, a cornercorner with one YS6 octahedra, corners with four YS7 pentagonal bipyramids, edges with two equivalent YS6 octahedra, and edges with six YS7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 58°. There are a spread of Y–S bond distances ranging from 2.69–2.77 Å. There are seven inequivalent S sites. In the first S site, S is bonded to one Ce and three Y atoms to form SCeY3 tetrahedra that share corners with three SCeY3 tetrahedra, corners with nine SCeY4 trigonal bipyramids, and edges with four SCe2Y3 trigonal bipyramids. In the second S site, S is bonded to four Y atoms to form distorted SY4 tetrahedra that share corners with three SCeY3 tetrahedra, corners with nine SCeY4 trigonal bipyramids, and edges with four SCeY4 trigonal bipyramids. In the third S site, S is bonded to one Ce and four Y atoms to form SCeY4 trigonal bipyramids that share corners with five SCeY3 tetrahedra, corners with four SY5 trigonal bipyramids, an edgeedge with one SY4 tetrahedra, and edges with five SCeY4 trigonal bipyramids. In the fourth S site, S is bonded to two equivalent Ce and three Y atoms to form SCe2Y3 trigonal bipyramids that share corners with five SCeY3 tetrahedra, corners with four SY5 trigonal bipyramids, an edgeedge with one SCeY3 tetrahedra, and edges with five SCeY4 trigonal bipyramids. In the fifth S site, S is bonded to five Y atoms to form distorted SY5 trigonal bipyramids that share corners with four equivalent SCeY3 tetrahedra, corners with six SCeY4 trigonal bipyramids, edges with three SCeY3 tetrahedra, and edges with six SCe2Y3 trigonal bipyramids. In the sixth S site, S is bonded to five Y atoms to form distorted SY5 trigonal bipyramids that share corners with four equivalent SY4 tetrahedra, corners with six SCeY4 trigonal bipyramids, edges with three SCeY3 tetrahedra, and edges with six SCeY4 trigonal bipyramids. In the seventh S site, S is bonded in a square co-planar geometry to two equivalent Ce and two equivalent Y atoms.

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2020-05-02. Materials Data on CeY4S7 by Materials Project. https://doi.org/10.17188/1741296

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