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DOE OSTI · 1698707

Materials Data on Tm3CrS6 by Materials Project

Abstract

Tm3CrS6 crystallizes in the orthorhombic Pnnm space group. The structure is three-dimensional. there are three inequivalent Tm3+ sites. In the first Tm3+ site, Tm3+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Tm–S bond distances ranging from 2.73–2.89 Å. In the second Tm3+ site, Tm3+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Tm–S bond distances ranging from 2.72–3.05 Å. In the third Tm3+ site, Tm3+ is bonded to seven S2- atoms to form distorted TmS7 pentagonal bipyramids that share a cornercorner with one CrS6 octahedra, edges with two equivalent CrS6 octahedra, and edges with two equivalent TmS7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 35°. There are a spread of Tm–S bond distances ranging from 2.69–2.83 Å. There are two inequivalent Cr3+ sites. In the first Cr3+ site, Cr3+ is bonded to six S2- atoms to form CrS6 octahedra that share edges with two equivalent CrS6 octahedra and edges with four equivalent TmS7 pentagonal bipyramids. There are two shorter (2.41 Å) and four longer (2.44 Å) Cr–S bond lengths. In the second Cr3+ site, Cr3+ is bonded to six S2- atoms to form CrS6 octahedra that share corners with two equivalent TmS7 pentagonal bipyramids and edges with two equivalent CrS6 octahedra. There are two shorter (2.34 Å) and four longer (2.47 Å) Cr–S bond lengths. There are six inequivalent S2- sites. In the first S2- site, S2- is bonded in a 5-coordinate geometry to five Tm3+ atoms. In the second S2- site, S2- is bonded in a 5-coordinate geometry to three Tm3+ and two equivalent Cr3+ atoms. In the third S2- site, S2- is bonded to three Tm3+ and one Cr3+ atom to form distorted STm3Cr trigonal pyramids that share corners with two equivalent STm4Cr square pyramids, corners with two equivalent STm5 trigonal bipyramids, corners with three equivalent STm3Cr trigonal pyramids, and a faceface with one STm5 trigonal bipyramid. In the fourth S2- site, S2- is bonded to five Tm3+ atoms to form distorted STm5 trigonal bipyramids that share corners with four equivalent STm4Cr square pyramids, corners with two equivalent STm3Cr trigonal pyramids, an edgeedge with one STm4Cr square pyramid, edges with two equivalent STm5 trigonal bipyramids, and a faceface with one STm3Cr trigonal pyramid. In the fifth S2- site, S2- is bonded to four Tm3+ and one Cr3+ atom to form distorted STm4Cr square pyramids that share a cornercorner with one STm4Cr square pyramid, corners with four equivalent STm5 trigonal bipyramids, corners with two equivalent STm3Cr trigonal pyramids, edges with two equivalent STm4Cr square pyramids, and an edgeedge with one STm5 trigonal bipyramid. In the sixth S2- site, S2- is bonded in a 5-coordinate geometry to three Tm3+ and two equivalent Cr3+ atoms.

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2020-05-01. Materials Data on Tm3CrS6 by Materials Project. https://doi.org/10.17188/1698707

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