Materials Data on K2Ho4Cu4S9 by Materials Project

Abstract

K2Ho4Cu4S9 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. K1+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of K–S bond distances ranging from 3.16–3.81 Å. There are two inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded to six S2- atoms to form HoS6 octahedra that share corners with three HoS6 octahedra, a cornercorner with one CuS4 tetrahedra, edges with five equivalent HoS6 octahedra, and edges with two equivalent CuS4 tetrahedra. The corner-sharing octahedra tilt angles range from 0–36°. There are a spread of Ho–S bond distances ranging from 2.67–2.81 Å. In the second Ho3+ site, Ho3+ is bonded to six S2- atoms to form HoS6 octahedra that share a cornercorner with one HoS6 octahedra, corners with four equivalent CuS4 tetrahedra, edges with four equivalent HoS6 octahedra, and edges with five CuS4 tetrahedra. The corner-sharing octahedral tilt angles are 36°. There are a spread of Ho–S bond distances ranging from 2.68–2.78 Å. There are two inequivalent Cu1+ sites. In the first Cu1+ site, Cu1+ is bonded to four S2- atoms to form CuS4 tetrahedra that share a cornercorner with one HoS6 octahedra, corners with four CuS4 tetrahedra, and edges with four HoS6 octahedra. The corner-sharing octahedral tilt angles are 5°. There are three shorter (2.35 Å) and one longer (2.47 Å) Cu–S bond lengths. In the second Cu1+ site, Cu1+ is bonded to four S2- atoms to form CuS4 tetrahedra that share corners with four equivalent HoS6 octahedra, corners with four CuS4 tetrahedra, edges with three equivalent HoS6 octahedra, and an edgeedge with one CuS4 tetrahedra. The corner-sharing octahedra tilt angles range from 14–60°. There are a spread of Cu–S bond distances ranging from 2.34–2.54 Å. There are five inequivalent S2- sites. In the first S2- site, S2- is bonded in a 6-coordinate geometry to two equivalent K1+, two Ho3+, and two equivalent Cu1+ atoms. In the second S2- site, S2- is bonded in a 7-coordinate geometry to two equivalent K1+, two equivalent Ho3+, and three Cu1+ atoms. In the third S2- site, S2- is bonded to two equivalent K1+, three equivalent Ho3+, and one Cu1+ atom to form distorted SK2Ho3Cu octahedra that share corners with two equivalent SKHo3Cu2 octahedra and edges with four equivalent SK2Ho3Cu octahedra. The corner-sharing octahedral tilt angles are 41°. In the fourth S2- site, S2- is bonded to one K1+, three equivalent Ho3+, and two equivalent Cu1+ atoms to form distorted SKHo3Cu2 octahedra that share corners with two equivalent SK2Ho3Cu octahedra and edges with four equivalent SKHo3Cu2 octahedra. The corner-sharing octahedral tilt angles are 41°. In the fifth S2- site, S2- is bonded in a distorted square co-planar geometry to two equivalent K1+ and four equivalent Ho3+ atoms.