Materials Data on MgCoO2 by Materials Project

Abstract

MgCoO2 is Caswellsilverite-like structured and crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with four CoO6 octahedra, edges with five CoO6 octahedra, and edges with seven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 1–2°. There are a spread of Mg–O bond distances ranging from 2.11–2.14 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with four CoO6 octahedra, edges with five CoO6 octahedra, and edges with seven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 1–2°. There are four shorter (2.12 Å) and two longer (2.13 Å) Mg–O bond lengths. There are two inequivalent Co2+ sites. In the first Co2+ site, Co2+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with two equivalent CoO6 octahedra, corners with four MgO6 octahedra, edges with five MgO6 octahedra, and edges with seven CoO6 octahedra. The corner-sharing octahedra tilt angles range from 1–2°. There are a spread of Co–O bond distances ranging from 2.12–2.20 Å. In the second Co2+ site, Co2+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with two equivalent CoO6 octahedra, corners with four MgO6 octahedra, edges with five MgO6 octahedra, and edges with seven CoO6 octahedra. The corner-sharing octahedra tilt angles range from 1–2°. There are a spread of Co–O bond distances ranging from 2.12–2.18 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to one Mg2+ and five Co2+ atoms to form OMgCo5 octahedra that share corners with six OMg3Co3 octahedra and edges with twelve OMgCo5 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the second O2- site, O2- is bonded to three equivalent Mg2+ and three Co2+ atoms to form a mixture of edge and corner-sharing OMg3Co3 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the third O2- site, O2- is bonded to three Mg2+ and three equivalent Co2+ atoms to form a mixture of edge and corner-sharing OMg3Co3 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the fourth O2- site, O2- is bonded to five Mg2+ and one Co2+ atom to form a mixture of edge and corner-sharing OMg5Co octahedra. The corner-sharing octahedra tilt angles range from 0–2°.