DOI: 10.17188/1672105
title: Materials Data on CaMg6CdO8 by Materials Project

description: CaMg6CdO8 is alpha Po-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with two equivalent CdO6 octahedra, corners with four equivalent CaO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.21 Å) and four longer (2.23 Å) Ca–O bond lengths. There are three inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, edges with four equivalent CaO6 octahedra, and edges with eight equivalent MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.22 Å) and four longer (2.23 Å) Mg–O bond lengths. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, edges with four equivalent CdO6 octahedra, and edges with eight equivalent MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.22 Å) and four longer (2.23 Å) Mg–O bond lengths. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six equivalent MgO6 octahedra, edges with two equivalent CaO6 octahedra, edges with two equivalent CdO6 octahedra, and edges with eight MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are one shorter (2.22 Å) and five longer (2.23 Å) Mg–O bond lengths. Cd2+ is bonded to six O2- atoms to form CdO6 octahedra that share corners with two equivalent CaO6 octahedra, corners with four equivalent CdO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.23 Å) and two longer (2.24 Å) Cd–O bond lengths. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to one Ca2+, four equivalent Mg2+, and one Cd2+ atom to form OCaMg4Cd octahedra that share corners with six equivalent OCaMg4Cd octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the second O2- site, O2- is bonded to six Mg2+ atoms to form OMg6 octahedra that share corners with six equivalent OMg6 octahedra and edges with twelve OCaMg4Cd octahedra. The corner-sharing octahedral tilt angles are 0°. In the third O2- site, O2- is bonded to two equivalent Ca2+ and four Mg2+ atoms to form OCa2Mg4 octahedra that share corners with six OCa2Mg4 octahedra and edges with twelve OCaMg4Cd octahedra. The corner-sharing octahedral tilt angles are 0°. In the fourth O2- site, O2- is bonded to four Mg2+ and two equivalent Cd2+ atoms to form OMg4Cd2 octahedra that share corners with six OCa2Mg4 octahedra and edges with twelve OCaMg4Cd octahedra. The corner-sharing octahedral tilt angles are 0°. In the fifth O2- site, O2- is bonded to four Mg2+ and two equivalent Cd2+ atoms to form OMg4Cd2 octahedra that share corners with six OCa2Mg4 octahedra and edges with twelve OCaMg4Cd octahedra. The corner-sharing octahedral tilt angles are 0°. Both O–Mg bond lengths are 2.22 Å.