DOI: 10.17188/1321123
title: Materials Data on MgCuO2 by Materials Project

description: CuOMgO crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four 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, a cornercorner with one CuO5 square pyramid, edges with seven MgO6 octahedra, and edges with two equivalent CuO5 square pyramids. The corner-sharing octahedral tilt angles are 8°. There are a spread of Mg–O bond distances ranging from 2.04–2.23 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, a cornercorner with one CuO5 square pyramid, edges with seven MgO6 octahedra, and edges with two equivalent CuO5 square pyramids. The corner-sharing octahedral tilt angles are 8°. There are a spread of Mg–O bond distances ranging from 2.03–2.26 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with two equivalent CuO5 square pyramids, edges with seven MgO6 octahedra, and edges with three CuO5 square pyramids. The corner-sharing octahedral tilt angles are 8°. There are a spread of Mg–O bond distances ranging from 2.04–2.20 Å. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with two equivalent CuO5 square pyramids, edges with seven MgO6 octahedra, and edges with three CuO5 square pyramids. The corner-sharing octahedral tilt angles are 8°. There are a spread of Mg–O bond distances ranging from 2.04–2.22 Å. There are four inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are a spread of Cu–O bond distances ranging from 1.95–2.01 Å. In the second Cu2+ site, Cu2+ is bonded to five O2- atoms to form CuO5 square pyramids that share corners with three MgO6 octahedra, edges with five MgO6 octahedra, and edges with two equivalent CuO5 square pyramids. The corner-sharing octahedra tilt angles range from 1–10°. There are a spread of Cu–O bond distances ranging from 1.96–2.46 Å. In the third Cu2+ site, Cu2+ is bonded to five O2- atoms to form CuO5 square pyramids that share corners with three MgO6 octahedra, edges with five MgO6 octahedra, and edges with two equivalent CuO5 square pyramids. The corner-sharing octahedra tilt angles range from 1–11°. There are a spread of Cu–O bond distances ranging from 1.96–2.46 Å. In the fourth Cu2+ site, Cu2+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are a spread of Cu–O bond distances ranging from 1.95–2.02 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded to one Mg2+ and four Cu2+ atoms to form OMgCu4 square pyramids that share a cornercorner with one OMg5Cu octahedra, corners with six OMg3Cu2 square pyramids, edges with two equivalent OMg5Cu octahedra, and edges with four OMgCu4 square pyramids. The corner-sharing octahedral tilt angles are 1°. In the second O2- site, O2- is bonded to three Mg2+ and two equivalent Cu2+ atoms to form OMg3Cu2 square pyramids that share corners with two equivalent OMg5Cu octahedra, corners with five OMgCu4 square pyramids, edges with three OMg5Cu octahedra, and edges with five OMgCu4 square pyramids. The corner-sharing octahedral tilt angles are 3°. In the third O2- site, O2- is bonded to three Mg2+ and two equivalent Cu2+ atoms to form distorted OMg3Cu2 square pyramids that share corners with two equivalent OMg5Cu octahedra, corners with five OMgCu4 square pyramids, edges with three OMg5Cu octahedra, and edges with five OMg3Cu2 square pyramids. The corner-sharing octahedral tilt angles are 3°. In the fourth O2- site, O2- is bonded to one Mg2+ and four Cu2+ atoms to form OMgCu4 square pyramids that share a cornercorner with one OMg5Cu octahedra, corners with six OMg3Cu2 square pyramids, edges with two equivalent OMg5Cu octahedra, and edges with four OMg3Cu2 square pyramids. The corner-sharing octahedral tilt angles are 1°. In the fifth O2- site, O2- is bonded to three Mg2+ and two equivalent Cu2+ atoms to form distorted OMg3Cu2 square pyramids that share corners with two equivalent OMg5Cu octahedra, corners with seven OMgCu4 square pyramids, edges with three OMg5Cu octahedra, and edges with three OMgCu4 square pyramids. The corner-sharing octahedral tilt angles are 7°. In the sixth O2- site, O2- is bonded to five Mg2+ and one Cu2+ atom to form distorted OMg5Cu octahedra that share corners with five OMgCu4 square pyramids, edges with four OMg5Cu octahedra, and edges with eight OMg3Cu2 square pyramids. In the seventh O2- site, O2- is bonded to three Mg2+ and two equivalent Cu2+ atoms to form distorted OMg3Cu2 square pyramids that share corners with two equivalent OMg5Cu octahedra, corners with seven OMgCu4 square pyramids, edges with three OMg5Cu octahedra, and edges with three OMgCu4 square pyramids. The corner-sharing octahedral tilt angles are 7°. In the eighth O2- site, O2- is bonded to five Mg2+ and one Cu2+ atom to form distorted OMg5Cu octahedra that share corners with five OMg3Cu2 square pyramids, edges with four OMg5Cu octahedra, and edges with eight OMgCu4 square pyramids.