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DOE OSTI · 1667143

Materials Data on Ce(TmS2)3 by Materials Project

Abstract

Ce(TmS2)3 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are three inequivalent Tm3+ sites. In the first Tm3+ site, Tm3+ is bonded to seven S2- atoms to form distorted TmS7 pentagonal bipyramids that share corners with three TmS6 octahedra, edges with two equivalent TmS6 octahedra, and edges with four equivalent TmS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 39–50°. There are a spread of Tm–S bond distances ranging from 2.67–2.90 Å. In the second Tm3+ site, Tm3+ is bonded to six S2- atoms to form TmS6 octahedra that share corners with three equivalent TmS6 octahedra, a cornercorner with one TmS7 pentagonal bipyramid, edges with four equivalent TmS6 octahedra, and edges with two equivalent TmS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 54–62°. There are a spread of Tm–S bond distances ranging from 2.65–2.75 Å. In the third Tm3+ site, Tm3+ is bonded to six S2- atoms to form TmS6 octahedra that share corners with three equivalent TmS6 octahedra, corners with two equivalent TmS7 pentagonal bipyramids, and edges with four equivalent TmS6 octahedra. The corner-sharing octahedra tilt angles range from 54–62°. There are a spread of Tm–S bond distances ranging from 2.64–2.77 Å. Ce3+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Ce–S bond distances ranging from 2.90–3.04 Å. There are six inequivalent S2- sites. In the first S2- site, S2- is bonded in a 4-coordinate geometry to four Tm3+ atoms. In the second S2- site, S2- is bonded to three Tm3+ and one Ce3+ atom to form distorted SCeTm3 trigonal pyramids that share corners with two equivalent SCe2Tm3 square pyramids, corners with four SCe2Tm3 trigonal bipyramids, corners with two equivalent SCeTm3 trigonal pyramids, edges with three equivalent SCe2Tm3 square pyramids, and edges with two equivalent SCe3Tm2 trigonal bipyramids. In the third S2- site, S2- is bonded in a rectangular see-saw-like geometry to four Tm3+ atoms. In the fourth S2- site, S2- is bonded to three equivalent Tm3+ and two equivalent Ce3+ atoms to form distorted SCe2Tm3 square pyramids that share corners with six SCe2Tm3 trigonal bipyramids, corners with two equivalent SCeTm3 trigonal pyramids, edges with four equivalent SCe2Tm3 square pyramids, edges with two SCe2Tm3 trigonal bipyramids, and edges with three equivalent SCeTm3 trigonal pyramids. In the fifth S2- site, S2- is bonded to three Tm3+ and two equivalent Ce3+ atoms to form distorted SCe2Tm3 trigonal bipyramids that share corners with two equivalent SCe2Tm3 square pyramids, corners with two equivalent SCe3Tm2 trigonal bipyramids, corners with three equivalent SCeTm3 trigonal pyramids, an edgeedge with one SCe2Tm3 square pyramid, and edges with five SCe2Tm3 trigonal bipyramids. In the sixth S2- site, S2- is bonded to two equivalent Tm3+ and three equivalent Ce3+ atoms to form distorted SCe3Tm2 trigonal bipyramids that share corners with four equivalent SCe2Tm3 square pyramids, corners with two equivalent SCe2Tm3 trigonal bipyramids, a cornercorner with one SCeTm3 trigonal pyramid, an edgeedge with one SCe2Tm3 square pyramid, edges with seven SCe2Tm3 trigonal bipyramids, and edges with two equivalent SCeTm3 trigonal pyramids.

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2020-07-15. Materials Data on Ce(TmS2)3 by Materials Project. https://doi.org/10.17188/1667143

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