Materials Data on Cr10Co4CuSe20 by Materials Project
Cr10Co4CuSe20 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are five inequivalent Cr3+ sites. In the first Cr3+ site, Cr3+ is bonded to six Se2- atoms to form CrSe6 octahedra that share corners with six CoSe6 octahedra, edges with six CrSe6 octahedra, and a faceface with one CoSe6 octahedra. The corner-sharing octahedra tilt angles range from 49–53°. There are three shorter (2.50 Å) and three longer (2.62 Å) Cr–Se bond lengths. In the second Cr3+ site, Cr3+ is bonded to six Se2- atoms to form CrSe6 octahedra that share corners with six equivalent CoSe6 octahedra, edges with six equivalent CrSe6 octahedra, and a faceface with one CoSe6 octahedra. The corner-sharing octahedra tilt angles range from 49–53°. There are a spread of Cr–Se bond distances ranging from 2.50–2.62 Å. In the third Cr3+ site, Cr3+ is bonded to six Se2- atoms to form CrSe6 octahedra that share corners with six CoSe6 octahedra, edges with six CrSe6 octahedra, and a faceface with one CoSe6 octahedra. The corner-sharing octahedra tilt angles range from 49–53°. There are three shorter (2.50 Å) and three longer (2.62 Å) Cr–Se bond lengths. In the fourth Cr3+ site, Cr3+ is bonded to six Se2- atoms to form CrSe6 octahedra that share corners with two equivalent CuSe6 octahedra, corners with four equivalent CoSe6 octahedra, edges with six CrSe6 octahedra, and a faceface with one CuSe6 octahedra. The corner-sharing octahedra tilt angles range from 50–53°. There are a spread of Cr–Se bond distances ranging from 2.51–2.64 Å. In the fifth Cr3+ site, Cr3+ is bonded to six Se2- atoms to form CrSe6 octahedra that share corners with two equivalent CoSe6 octahedra, corners with four equivalent CuSe6 octahedra, edges with six CrSe6 octahedra, and a faceface with one CoSe6 octahedra. The corner-sharing octahedra tilt angles range from 48–52°. There are a spread of Cr–Se bond distances ranging from 2.48–2.63 Å. There are two inequivalent Co2+ sites. In the first Co2+ site, Co2+ is bonded to six Se2- atoms to form CoSe6 octahedra that share corners with twelve CrSe6 octahedra, edges with two equivalent CoSe6 octahedra, and faces with two CrSe6 octahedra. The corner-sharing octahedra tilt angles range from 48–53°. There are four shorter (2.47 Å) and two longer (2.51 Å) Co–Se bond lengths. In the second Co2+ site, Co2+ is bonded to six Se2- atoms to form CoSe6 octahedra that share corners with twelve CrSe6 octahedra, edges with two equivalent CoSe6 octahedra, and faces with two CrSe6 octahedra. The corner-sharing octahedra tilt angles range from 49–53°. There are two shorter (2.48 Å) and four longer (2.51 Å) Co–Se bond lengths. Cu2+ is bonded to six Se2- atoms to form CuSe6 octahedra that share corners with twelve CrSe6 octahedra, edges with two equivalent CuSe6 octahedra, and faces with two equivalent CrSe6 octahedra. The corner-sharing octahedra tilt angles range from 50–52°. There are two shorter (2.54 Å) and four longer (2.61 Å) Cu–Se bond lengths. There are ten inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a rectangular see-saw-like geometry to three Cr3+ and one Co2+ atom. In the second Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to three Cr3+ and one Cu2+ atom. In the third Se2- site, Se2- is bonded in a rectangular see-saw-like geometry to three Cr3+ and one Co2+ atom. In the fourth Se2- site, Se2- is bonded in a 5-coordinate geometry to three Cr3+ and two equivalent Co2+ atoms. In the fifth Se2- site, Se2- is bonded in a 5-coordinate geometry to three equivalent Cr3+ and two equivalent Co2+ atoms. In the sixth Se2- site, Se2- is bonded in a 5-coordinate geometry to three Cr3+ and two equivalent Co2+ atoms. In the seventh Se2- site, Se2- is bonded in a 5-coordinate geometry to three Cr3+ and two equivalent Co2+ atoms. In the eighth Se2- site, Se2- is bonded in a 5-coordinate geometry to three Cr3+ and two equivalent Cu2+ atoms. In the ninth Se2- site, Se2- is bonded in a rectangular see-saw-like geometry to three Cr3+ and one Co2+ atom. In the tenth Se2- site, Se2- is bonded in a rectangular see-saw-like geometry to three equivalent Cr3+ and one Co2+ atom.