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DOE OSTI · 1714913

Materials Data on Nd4(TmS2)11 by Materials Project

Abstract

Nd4(TmS2)11 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are six 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 2.67–2.86 Å. In the second Tm3+ site, Tm3+ is bonded to six S2- atoms to form a mixture of edge and corner-sharing TmS6 octahedra. The corner-sharing octahedra tilt angles range from 48–59°. There are a spread of Tm–S bond distances ranging from 2.62–2.75 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 TmS6 octahedra. The corner-sharing octahedra tilt angles range from 50–63°. There are a spread of Tm–S bond distances ranging from 2.63–2.76 Å. In the fourth 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 50–63°. There are a spread of Tm–S bond distances ranging from 2.64–2.74 Å. In the fifth Tm3+ site, Tm3+ is bonded to six S2- atoms to form a mixture of edge and corner-sharing TmS6 octahedra. The corner-sharing octahedra tilt angles range from 48–59°. There are a spread of Tm–S bond distances ranging from 2.63–2.74 Å. In the sixth Tm3+ site, Tm3+ is bonded to six S2- atoms to form a mixture of edge and corner-sharing TmS6 octahedra. The corner-sharing octahedral tilt angles are 55°. There are four shorter (2.70 Å) and two longer (2.72 Å) Tm–S bond lengths. There are two inequivalent Nd+2.75+ sites. In the first Nd+2.75+ site, Nd+2.75+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Nd–S bond distances ranging from 2.90–3.03 Å. In the second Nd+2.75+ site, Nd+2.75+ is bonded in a 7-coordinate geometry to eight S2- atoms. There are a spread of Nd–S bond distances ranging from 2.89–3.41 Å. There are eleven inequivalent S2- sites. In the first S2- site, S2- is bonded to three Tm3+ and two equivalent Nd+2.75+ atoms to form distorted SNd2Tm3 trigonal bipyramids that share corners with two equivalent SNd2Tm3 square pyramids, corners with two equivalent SNd3Tm2 trigonal bipyramids, corners with two SNdTm3 trigonal pyramids, an edgeedge with one SNd2Tm3 square pyramid, edges with five SNd2Tm3 trigonal bipyramids, and edges with two equivalent STm4 trigonal pyramids. In the second S2- site, S2- is bonded in a rectangular see-saw-like geometry to four Tm3+ atoms. In the third S2- site, S2- is bonded in a 4-coordinate geometry to three Tm3+ and one Nd+2.75+ atom. In the fourth S2- site, S2- is bonded to three Tm3+ and two equivalent Nd+2.75+ atoms to form distorted SNd2Tm3 square pyramids that share corners with six SNd2Tm3 trigonal bipyramids, corners with two equivalent SNdTm3 trigonal pyramids, edges with four SNd2Tm3 square pyramids, edges with two SNd2Tm3 trigonal bipyramids, and an edgeedge with one SNdTm3 trigonal pyramid. In the fifth S2- site, S2- is bonded to three Tm3+ and two equivalent Nd+2.75+ atoms to form distorted SNd2Tm3 square pyramids that share corners with two equivalent SNd2Tm3 square pyramids, corners with four SNd3Tm2 trigonal bipyramids, edges with five SNd2Tm3 square pyramids, an edgeedge with one SNd3Tm2 trigonal bipyramid, and edges with two equivalent SNdTm3 trigonal pyramids. In the sixth S2- site, S2- is bonded to three Tm3+ and two equivalent Nd+2.75+ atoms to form distorted SNd2Tm3 square pyramids that share corners with four SNd2Tm3 square pyramids, corners with two equivalent SNd3Tm2 trigonal bipyramids, corners with two equivalent SNdTm3 trigonal pyramids, edges with four SNd2Tm3 square pyramids, and edges with three SNd3Tm2 trigonal bipyramids. In the seventh S2- site, S2- is bonded to two equivalent Tm3+ and three Nd+2.75+ atoms to form distorted SNd3Tm2 trigonal bipyramids that share corners with six SNd2Tm3 square pyramids, corners with four equivalent STm4 trigonal pyramids, edges with two SNd2Tm3 square pyramids, edges with six SNd2Tm3 trigonal bipyramids, and edges with three SNdTm3 trigonal pyramids. In the eighth S2- site, S2- is bonded to three Tm3+ and one Nd+2.75+ atom to form distorted SNdTm3 trigonal pyramids that share corners with four SNd2Tm3 square pyramids, corners with two SNd2Tm3 trigonal bipyramids, corners with five SNdTm3 trigonal pyramids, edges with three SNd2Tm3 square pyramids, and edges with two equivalent SNd3Tm2 trigonal bipyramids. In the ninth S2- site, S2- is bonded in a rectangular see-saw-like geometry to four Tm3+ atoms. In the tenth S2- site, S2- is bonded to four Tm3+ atoms to form distorted STm4 trigonal pyramids that share corners with five SNd2Tm3 trigonal bipyramids, corners with five SNdTm3 trigonal pyramids, edges with three SNd2Tm3 trigonal bipyramids, and edges with two equivalent STm4 trigonal pyramids. In the eleventh S2- site, S2- is bonded to two equivalent Tm3+ and three Nd+2.75+ atoms to form distorted SNd3Tm2 trigonal bipyramids that share corners with four SNd2Tm3 square pyramids, corners with two equivalent SNd2Tm3 trigonal bipyramids, a cornercorner with one SNdTm3 trigonal pyramid, edges with three SNd2Tm3 square pyramids, and edges with five SNd2Tm3 trigonal bipyramids.

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2020-05-02. Materials Data on Nd4(TmS2)11 by Materials Project. https://doi.org/10.17188/1714913

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