Materials Data on Ba6Co25S27 by Materials Project
Ba6Co25S27 crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Ba2+ is bonded in a 9-coordinate geometry to nine S2- atoms. There are a spread of Ba–S bond distances ranging from 3.05–3.44 Å. There are two inequivalent Co+1.68+ sites. In the first Co+1.68+ site, Co+1.68+ is bonded to four S2- atoms to form CoS4 tetrahedra that share a cornercorner with one CoS6 octahedra, corners with five equivalent CoS4 tetrahedra, and edges with three equivalent CoS4 tetrahedra. The corner-sharing octahedral tilt angles are 54°. There are three shorter (2.16 Å) and one longer (2.24 Å) Co–S bond lengths. In the second Co+1.68+ site, Co+1.68+ is bonded to six equivalent S2- atoms to form corner-sharing CoS6 octahedra. All Co–S bond lengths are 2.39 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a 5-coordinate geometry to five Co+1.68+ atoms. In the second S2- site, S2- is bonded in a distorted trigonal non-coplanar geometry to three equivalent Ba2+ and three equivalent Co+1.68+ atoms. In the third S2- site, S2- is bonded in a 6-coordinate geometry to two equivalent Ba2+ and four equivalent Co+1.68+ atoms. In the fourth S2- site, S2- is bonded in an octahedral geometry to six equivalent Ba2+ atoms.