Materials Data on Cr6Cd(CuO6)2 by Materials Project

Abstract

Cr6Cd(CuO6)2 is Spinel-derived structured and crystallizes in the tetragonal I-4 space group. The structure is three-dimensional. there are three inequivalent Cr3+ sites. In the first Cr3+ site, Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with three CuO4 tetrahedra, corners with three equivalent CdO4 tetrahedra, and edges with six CrO6 octahedra. There are a spread of Cr–O bond distances ranging from 2.01–2.06 Å. In the second Cr3+ site, Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share a cornercorner with one CdO4 tetrahedra, corners with five CuO4 tetrahedra, and edges with six CrO6 octahedra. There are a spread of Cr–O bond distances ranging from 1.99–2.04 Å. In the third Cr3+ site, Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with two equivalent CdO4 tetrahedra, corners with four CuO4 tetrahedra, and edges with six CrO6 octahedra. There are a spread of Cr–O bond distances ranging from 2.01–2.06 Å. There are three inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded to four equivalent O2- atoms to form CuO4 tetrahedra that share corners with twelve CrO6 octahedra. The corner-sharing octahedra tilt angles range from 57–63°. All Cu–O bond lengths are 2.01 Å. In the second Cu2+ site, Cu2+ is bonded to four O2- atoms to form CuO4 tetrahedra that share corners with twelve CrO6 octahedra. The corner-sharing octahedra tilt angles range from 56–64°. There are two shorter (2.03 Å) and two longer (2.05 Å) Cu–O bond lengths. In the third Cu2+ site, Cu2+ is bonded to four equivalent O2- atoms to form CuO4 tetrahedra that share corners with twelve CrO6 octahedra. The corner-sharing octahedra tilt angles range from 58–59°. All Cu–O bond lengths are 2.06 Å. Cd2+ is bonded to four O2- atoms to form CdO4 tetrahedra that share corners with twelve CrO6 octahedra. The corner-sharing octahedra tilt angles range from 60–63°. All Cd–O bond lengths are 2.14 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded to three Cr3+ and one Cd2+ atom to form distorted OCr3Cd tetrahedra that share corners with three OCr3Cd tetrahedra, corners with six OCr3Cu trigonal pyramids, and an edgeedge with one OCr3Cd tetrahedra. In the second O2- site, O2- is bonded to three equivalent Cr3+ and one Cd2+ atom to form distorted OCr3Cd tetrahedra that share corners with three OCr3Cd tetrahedra, corners with nine OCr3Cu trigonal pyramids, and edges with three equivalent OCr3Cd tetrahedra. In the third O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Cr3+ and one Cu2+ atom. In the fourth O2- site, O2- is bonded to three Cr3+ and one Cu2+ atom to form distorted OCr3Cu trigonal pyramids that share corners with seven OCr3Cd tetrahedra, a cornercorner with one OCr3Cu trigonal pyramid, and edges with three OCr3Cu trigonal pyramids. In the fifth O2- site, O2- is bonded to three Cr3+ and one Cu2+ atom to form distorted OCr3Cu trigonal pyramids that share corners with eight OCr3Cd tetrahedra, corners with three equivalent OCr3Cu trigonal pyramids, and edges with three OCr3Cu trigonal pyramids. In the sixth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three equivalent Cr3+ and one Cu2+ atom.