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DOE OSTI · 1726704

Materials Data on Yb4MnS7 by Materials Project

Abstract

Yb4MnS7 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are four inequivalent Yb3+ sites. In the first Yb3+ site, Yb3+ is bonded to five S2- atoms to form distorted YbS5 square pyramids that share corners with two equivalent YbS6 octahedra, corners with two equivalent MnS6 octahedra, corners with two equivalent YbS7 pentagonal bipyramids, edges with three equivalent YbS6 octahedra, and edges with two equivalent YbS5 square pyramids. The corner-sharing octahedra tilt angles range from 19–52°. There are a spread of Yb–S bond distances ranging from 2.66–2.84 Å. In the second Yb3+ site, Yb3+ is bonded to seven S2- atoms to form distorted YbS7 pentagonal bipyramids that share corners with six YbS6 octahedra, corners with two equivalent YbS5 square pyramids, edges with two equivalent MnS6 octahedra, edges with four YbS6 octahedra, and faces with two equivalent YbS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 26–61°. There are a spread of Yb–S bond distances ranging from 2.77–3.03 Å. In the third Yb3+ site, Yb3+ is bonded to six S2- atoms to form distorted YbS6 octahedra that share a cornercorner with one YbS6 octahedra, a cornercorner with one MnS6 octahedra, corners with four equivalent YbS7 pentagonal bipyramids, corners with two equivalent YbS5 square pyramids, edges with two equivalent YbS6 octahedra, an edgeedge with one YbS7 pentagonal bipyramid, and edges with three equivalent YbS5 square pyramids. The corner-sharing octahedra tilt angles range from 59–64°. There are a spread of Yb–S bond distances ranging from 2.67–2.99 Å. In the fourth Yb3+ site, Yb3+ is bonded to six S2- atoms to form distorted YbS6 octahedra that share a cornercorner with one YbS6 octahedra, corners with two equivalent MnS6 octahedra, corners with two equivalent YbS7 pentagonal bipyramids, a cornercorner with one SYb4S trigonal bipyramid, edges with two equivalent YbS6 octahedra, edges with three equivalent MnS6 octahedra, and edges with three equivalent YbS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 21–64°. There are a spread of Yb–S bond distances ranging from 2.65–3.14 Å. Mn2+ is bonded to six S2- atoms to form MnS6 octahedra that share corners with three YbS6 octahedra, corners with two equivalent YbS5 square pyramids, corners with two equivalent SYb4S trigonal bipyramids, edges with two equivalent MnS6 octahedra, edges with three equivalent YbS6 octahedra, and edges with two equivalent YbS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 21–59°. There are a spread of Mn–S bond distances ranging from 2.26–2.55 Å. There are seven inequivalent S2- sites. In the first S2- site, S2- is bonded in a 5-coordinate geometry to four Yb3+ and one Mn2+ atom. In the second S2- site, S2- is bonded in a 2-coordinate geometry to one Yb3+, two equivalent Mn2+, and one S2- atom. The S–S bond length is 2.09 Å. In the third S2- site, S2- is bonded to four Yb3+ and one S2- atom to form distorted SYb4S trigonal bipyramids that share a cornercorner with one YbS6 octahedra, corners with two equivalent MnS6 octahedra, corners with two equivalent SYb4 tetrahedra, corners with four equivalent SYb5 trigonal bipyramids, and edges with three SYb4S trigonal bipyramids. The corner-sharing octahedra tilt angles range from 45–67°. In the fourth S2- site, S2- is bonded to five Yb3+ atoms to form distorted SYb5 trigonal bipyramids that share corners with two equivalent SYb3Mn2 square pyramids, corners with four equivalent SYb4 tetrahedra, corners with four equivalent SYb4S trigonal bipyramids, an edgeedge with one SYb4 tetrahedra, and edges with three SYb4S trigonal bipyramids. In the fifth S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb3+ and one Mn2+ atom. In the sixth S2- site, S2- is bonded to four Yb3+ atoms to form SYb4 tetrahedra that share corners with two equivalent SYb4 tetrahedra, corners with six SYb4S trigonal bipyramids, edges with two equivalent SYb3Mn2 square pyramids, and an edgeedge with one SYb5 trigonal bipyramid. In the seventh S2- site, S2- is bonded to three Yb3+ and two equivalent Mn2+ atoms to form distorted SYb3Mn2 square pyramids that share corners with two equivalent SYb5 trigonal bipyramids, edges with two equivalent SYb3Mn2 square pyramids, and edges with two equivalent SYb4 tetrahedra.

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2020-05-03. Materials Data on Yb4MnS7 by Materials Project. https://doi.org/10.17188/1726704

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