Materials Data on Nb3CrSe6 by Materials Project
Nb3CrSe6 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 Se2- atoms to form distorted NbSe6 pentagonal pyramids that share corners with three equivalent CrSe6 octahedra, edges with six NbSe6 pentagonal pyramids, and a faceface with one CrSe6 octahedra. The corner-sharing octahedral tilt angles are 47°. There are three shorter (2.62 Å) and three longer (2.65 Å) Nb–Se bond lengths. In the second Nb3+ site, Nb3+ is bonded to six equivalent Se2- atoms to form distorted NbSe6 pentagonal pyramids that share corners with six equivalent CrSe6 octahedra and edges with six equivalent NbSe6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 47°. All Nb–Se bond lengths are 2.62 Å. Cr3+ is bonded to six equivalent Se2- atoms to form CrSe6 octahedra that share corners with twelve NbSe6 pentagonal pyramids and faces with two equivalent NbSe6 pentagonal pyramids. All Cr–Se bond lengths are 2.54 Å. Se2- is bonded in a distorted rectangular see-saw-like geometry to three Nb3+ and one Cr3+ atom.