Materials Data on Nb3CrS6 by Materials Project
CrNb3S6 is Ilmenite-like structured and crystallizes in the hexagonal P6_322 space group. The structure is three-dimensional. there are two inequivalent Nb3+ sites. In the first Nb3+ site, Nb3+ is bonded to six equivalent S2- atoms to form distorted NbS6 pentagonal pyramids that share corners with six equivalent CrS6 octahedra and edges with six equivalent NbS6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 46°. All Nb–S bond lengths are 2.50 Å. In the second Nb3+ site, Nb3+ is bonded to six equivalent S2- atoms to form distorted NbS6 pentagonal pyramids that share corners with three equivalent CrS6 octahedra, edges with six NbS6 pentagonal pyramids, and a faceface with one CrS6 octahedra. The corner-sharing octahedral tilt angles are 46°. There are three shorter (2.49 Å) and three longer (2.51 Å) Nb–S bond lengths. Cr3+ is bonded to six equivalent S2- atoms to form CrS6 octahedra that share corners with twelve NbS6 pentagonal pyramids and faces with two equivalent NbS6 pentagonal pyramids. All Cr–S bond lengths are 2.42 Å. S2- is bonded in a distorted rectangular see-saw-like geometry to three Nb3+ and one Cr3+ atom.