Materials Data on CsMg6CO8 by Materials Project

Abstract

CsMg6CO8 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Cs1+ is bonded to six O2- atoms to form CsO6 octahedra that share corners with four equivalent CsO6 octahedra and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.29 Å) and two longer (2.59 Å) Cs–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 CsO6 octahedra, and edges with eight equivalent MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.23 Å) and four longer (2.29 Å) Mg–O bond lengths. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form a mixture of corner and edge-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.19 Å) and four longer (2.29 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 CsO6 octahedra, and edges with eight MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–9°. There are a spread of Mg–O bond distances ranging from 2.01–2.41 Å. C3+ is bonded in a distorted linear geometry to two equivalent O2- atoms. Both C–O bond lengths are 1.83 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to one Cs1+, four equivalent Mg2+, and one C3+ atom to form OCsMg4C octahedra that share corners with six equivalent OCsMg4C octahedra and edges with eight OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–9°. 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 eight OCsMg4C octahedra. The corner-sharing octahedra tilt angles range from 0–9°. In the third O2- site, O2- is bonded to two equivalent Cs1+ and four Mg2+ atoms to form OCs2Mg4 octahedra that share corners with four equivalent OCs2Mg4 octahedra and edges with twelve OCsMg4C octahedra. The corner-sharing octahedral tilt angles are 0°. In the fourth O2- site, O2- is bonded in a distorted square co-planar geometry to four Mg2+ atoms. In the fifth O2- site, O2- is bonded to two equivalent Cs1+ and four Mg2+ atoms to form OCs2Mg4 octahedra that share corners with four equivalent OCs2Mg4 octahedra and edges with twelve OCsMg4C octahedra. The corner-sharing octahedral tilt angles are 0°. Both O–Mg bond lengths are 2.41 Å.