Materials Data on Ti2CrSe4 by Materials Project
Ti2CrSe4 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Ti3+ is bonded to six Se2- atoms to form TiSe6 octahedra that share corners with six equivalent CrSe6 octahedra, edges with six equivalent TiSe6 octahedra, and a faceface with one CrSe6 octahedra. The corner-sharing octahedra tilt angles range from 49–51°. There are a spread of Ti–Se bond distances ranging from 2.54–2.70 Å. Cr2+ is bonded to six Se2- atoms to form CrSe6 octahedra that share corners with twelve equivalent TiSe6 octahedra, edges with two equivalent CrSe6 octahedra, and faces with two equivalent TiSe6 octahedra. The corner-sharing octahedra tilt angles range from 49–51°. There are two shorter (2.56 Å) and four longer (2.58 Å) Cr–Se bond lengths. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to three equivalent Ti3+ and two equivalent Cr2+ atoms to form a mixture of distorted corner and edge-sharing SeTi3Cr2 trigonal bipyramids. In the second Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to three equivalent Ti3+ and one Cr2+ atom.