DOI: 10.17188/1683553
title: Materials Data on Yb4FeS7 by Materials Project

description: Yb4FeS7 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are four inequivalent Yb+2.75+ sites. In the first Yb+2.75+ site, Yb+2.75+ is bonded to seven S2- atoms to form distorted YbS7 square pyramids that share corners with two equivalent YbS6 octahedra, corners with four equivalent FeS6 octahedra, corners with two equivalent YbS7 pentagonal bipyramids, corners with two equivalent SYb4S trigonal bipyramids, an edgeedge with one FeS6 octahedra, edges with three equivalent YbS6 octahedra, and faces with two equivalent YbS7 square pyramids. The corner-sharing octahedra tilt angles range from 15–51°. There are a spread of Yb–S bond distances ranging from 2.66–3.28 Å. In the second Yb+2.75+ site, Yb+2.75+ is bonded to seven S2- atoms to form distorted YbS7 pentagonal bipyramids that share corners with four equivalent YbS6 octahedra, corners with two equivalent YbS7 square pyramids, an edgeedge with one YbS6 octahedra, edges with two equivalent FeS6 octahedra, and faces with two equivalent YbS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 27–62°. There are a spread of Yb–S bond distances ranging from 2.76–3.02 Å. In the third Yb+2.75+ site, Yb+2.75+ is bonded to six S2- atoms to form distorted YbS6 octahedra that share a cornercorner with one FeS6 octahedra, corners with four equivalent YbS7 pentagonal bipyramids, corners with two equivalent YbS7 square pyramids, edges with two equivalent YbS6 octahedra, an edgeedge with one YbS7 pentagonal bipyramid, and edges with three equivalent YbS7 square pyramids. The corner-sharing octahedral tilt angles are 59°. There are a spread of Yb–S bond distances ranging from 2.65–2.97 Å. In the fourth Yb+2.75+ site, Yb+2.75+ is bonded in a 6-coordinate geometry to six S2- atoms. There are a spread of Yb–S bond distances ranging from 2.66–3.14 Å. Fe3+ is bonded to six S2- atoms to form FeS6 octahedra that share a cornercorner with one YbS6 octahedra, corners with four equivalent YbS7 square pyramids, corners with two equivalent SYb4S trigonal bipyramids, edges with two equivalent FeS6 octahedra, edges with two equivalent YbS7 pentagonal bipyramids, and an edgeedge with one YbS7 square pyramid. The corner-sharing octahedral tilt angles are 59°. There are a spread of Fe–S bond distances ranging from 2.24–2.48 Å. There are seven inequivalent S2- sites. In the first S2- site, S2- is bonded in a 5-coordinate geometry to four Yb+2.75+ and one Fe3+ atom. In the second S2- site, S2- is bonded in a 2-coordinate geometry to three Yb+2.75+, two equivalent Fe3+, and one S2- atom. The S–S bond length is 2.09 Å. In the third S2- site, S2- is bonded to four Yb+2.75+ and one S2- atom to form distorted SYb4S trigonal bipyramids that share corners with two equivalent FeS6 octahedra, corners with two equivalent YbS7 square pyramids, corners with two equivalent SYb4 tetrahedra, corners with four equivalent SYb5 trigonal bipyramids, and edges with three SYb4S trigonal bipyramids. The corner-sharing octahedral tilt angles are 66°. In the fourth S2- site, S2- is bonded to five Yb+2.75+ atoms to form distorted SYb5 trigonal bipyramids that share corners with two equivalent SYb3Fe2 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 Yb+2.75+ and one Fe3+ atom. In the sixth S2- site, S2- is bonded to four Yb+2.75+ atoms to form SYb4 tetrahedra that share corners with two equivalent SYb4 tetrahedra, corners with six SYb4S trigonal bipyramids, edges with two equivalent SYb3Fe2 square pyramids, and an edgeedge with one SYb5 trigonal bipyramid. In the seventh S2- site, S2- is bonded to three Yb+2.75+ and two equivalent Fe3+ atoms to form distorted SYb3Fe2 square pyramids that share corners with two equivalent SYb5 trigonal bipyramids, edges with two equivalent SYb3Fe2 square pyramids, and edges with two equivalent SYb4 tetrahedra.