DOI: 10.17188/1757444
title: Materials Data on Ho4FeS7 by Materials Project

description: Ho4FeS7 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are four inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of Ho–S bond distances ranging from 2.72–3.08 Å. In the second Ho3+ site, Ho3+ is bonded to seven S2- atoms to form distorted HoS7 pentagonal bipyramids that share corners with two equivalent FeS6 octahedra, corners with six HoS6 octahedra, edges with four HoS6 octahedra, and faces with two equivalent HoS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 22–68°. There are a spread of Ho–S bond distances ranging from 2.69–2.99 Å. In the third Ho3+ site, Ho3+ is bonded to six S2- atoms to form HoS6 octahedra that share a cornercorner with one HoS6 octahedra, a cornercorner with one FeS6 octahedra, corners with two equivalent HoS7 pentagonal bipyramids, edges with two equivalent HoS6 octahedra, and edges with three equivalent HoS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 50–52°. There are a spread of Ho–S bond distances ranging from 2.65–2.70 Å. In the fourth Ho3+ site, Ho3+ is bonded to six S2- atoms to form HoS6 octahedra that share a cornercorner with one HoS6 octahedra, corners with two equivalent FeS6 octahedra, corners with four equivalent HoS7 pentagonal bipyramids, edges with two equivalent HoS6 octahedra, edges with three equivalent FeS6 octahedra, and an edgeedge with one HoS7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 4–50°. There are a spread of Ho–S bond distances ranging from 2.66–2.77 Å. Fe2+ is bonded to six S2- atoms to form FeS6 octahedra that share corners with three HoS6 octahedra, corners with two equivalent HoS7 pentagonal bipyramids, edges with two equivalent FeS6 octahedra, and edges with three equivalent HoS6 octahedra. The corner-sharing octahedra tilt angles range from 4–52°. There are a spread of Fe–S bond distances ranging from 2.47–2.63 Å. There are seven inequivalent S2- sites. In the first S2- site, S2- is bonded to four Ho3+ and one Fe2+ atom to form distorted SHo4Fe trigonal bipyramids that share corners with five SHo3Fe tetrahedra, corners with two equivalent SHo5 trigonal bipyramids, edges with two equivalent SHo3Fe2 square pyramids, an edgeedge with one SHo4 tetrahedra, and edges with two equivalent SHo4Fe trigonal bipyramids. In the second S2- site, S2- is bonded to three Ho3+ and two equivalent Fe2+ atoms to form distorted SHo3Fe2 square pyramids that share corners with five SHo3Fe tetrahedra, corners with two equivalent SHo5 trigonal bipyramids, edges with two equivalent SHo3Fe2 square pyramids, an edgeedge with one SHo3Fe tetrahedra, and edges with three SHo4Fe trigonal bipyramids. In the third S2- site, S2- is bonded to five Ho3+ atoms to form distorted SHo5 trigonal bipyramids that share corners with two equivalent SHo3Fe2 square pyramids, corners with four equivalent SHo3Fe tetrahedra, corners with two equivalent SHo4Fe trigonal bipyramids, an edgeedge with one SHo3Fe2 square pyramid, edges with three SHo3Fe tetrahedra, and edges with two equivalent SHo5 trigonal bipyramids. In the fourth S2- site, S2- is bonded in a 5-coordinate geometry to five Ho3+ atoms. In the fifth S2- site, S2- is bonded to three Ho3+ and one Fe2+ atom to form distorted SHo3Fe tetrahedra that share corners with four equivalent SHo3Fe2 square pyramids, corners with three SHo3Fe tetrahedra, corners with five SHo4Fe trigonal bipyramids, an edgeedge with one SHo3Fe2 square pyramid, and an edgeedge with one SHo5 trigonal bipyramid. In the sixth S2- site, S2- is bonded to four Ho3+ atoms to form distorted SHo4 tetrahedra that share a cornercorner with one SHo3Fe2 square pyramid, corners with three SHo3Fe tetrahedra, corners with four equivalent SHo4Fe trigonal bipyramids, and edges with three SHo4Fe trigonal bipyramids. In the seventh S2- site, S2- is bonded in a rectangular see-saw-like geometry to two equivalent Ho3+ and two equivalent Fe2+ atoms.