Materials Data on Mg(CuO2)2 by Materials Project

MgCu2O4 is Spinel-like structured and crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are eight inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to four O2- atoms to form MgO4 tetrahedra that share corners with three MgO6 octahedra and corners with nine CuO6 octahedra. The corner-sharing octahedra tilt angles range from 56–60°. There is three shorter (1.98 Å) and one longer (2.01 Å) Mg–O bond length. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with three MgO4 tetrahedra, corners with three CuO4 tetrahedra, and edges with six CuO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.04–2.09 Å. In the third Mg2+ site, Mg2+ is bonded to four O2- atoms to form MgO4 tetrahedra that share corners with three MgO6 octahedra and corners with nine CuO6 octahedra. The corner-sharing octahedra tilt angles range from 57–60°. There are a spread of Mg–O bond distances ranging from 1.98–2.03 Å. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four CuO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with five CuO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.04–2.09 Å. In the fifth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six CuO4 tetrahedra, edges with two MgO6 octahedra, and edges with four equivalent CuO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.05–2.08 Å. In the sixth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six CuO4 tetrahedra, edges with two MgO6 octahedra, and edges with four CuO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.05–2.12 Å. In the seventh Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five CuO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with five CuO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.04–2.09 Å. In the eighth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six CuO4 tetrahedra, edges with two MgO6 octahedra, and edges with four CuO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.05–2.10 Å. There are twelve inequivalent Cu3+ sites. In the first Cu3+ site, Cu3+ is bonded to six O2- atoms to form CuO6 octahedra that share corners with three MgO4 tetrahedra, corners with three CuO4 tetrahedra, edges with two equivalent MgO6 octahedra, and edges with four CuO6 octahedra. There are a spread of Cu–O bond distances ranging from 1.95–2.09 Å. In the second Cu3+ site, Cu3+ is bonded to six O2- atoms to form CuO6 octahedra that share corners with three equivalent MgO4 tetrahedra, corners with three equivalent CuO4 tetrahedra, edges with two MgO6 octahedra, and edges with four CuO6 octahedra. There are a spread of Cu–O bond distances ranging from 1.95–2.07 Å. In the third Cu3+ site, Cu3+ is bonded to four O2- atoms to form CuO4 tetrahedra that share corners with six MgO6 octahedra and corners with six CuO6 octahedra. The corner-sharing octahedra tilt angles range from 56–59°. All Cu–O bond lengths are 1.93 Å. In the fourth Cu3+ site, Cu3+ is bonded to six O2- atoms to form CuO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four CuO4 tetrahedra, edges with three MgO6 octahedra, and edges with three CuO6 octahedra. There are a spread of Cu–O bond distances ranging from 1.91–2.04 Å. In the fifth Cu3+ site, Cu3+ is bonded to four O2- atoms to form CuO4 tetrahedra that share corners with three MgO6 octahedra and corners with nine CuO6 octahedra. The corner-sharing octahedra tilt angles range from 56–62°. There are a spread of Cu–O bond distances ranging from 1.89–1.98 Å. In the sixth Cu3+ site, Cu3+ is bonded to four O2- atoms to form CuO4 tetrahedra that share corners with six MgO6 octahedra and corners with six CuO6 octahedra. The corner-sharing octahedra tilt angles range from 55–60°. There are a spread of Cu–O bond distances ranging from 1.90–1.92 Å. In the seventh Cu3+ site, Cu3+ is bonded to six O2- atoms to form CuO6 octahedra that share corners with six CuO4 tetrahedra, edges with two equivalent CuO6 octahedra, and edges with four MgO6 octahedra. There are a spread of Cu–O bond distances ranging from 1.92–2.04 Å. In the eighth Cu3+ site, Cu3+ is bonded to four O2- atoms to form CuO4 tetrahedra that share corners with six MgO6 octahedra and corners with six CuO6 octahedra. The corner-sharing octahedra tilt angles range from 55–61°. There is one shorter (1.91 Å) and three longer (1.94 Å) Cu–O bond length. In the ninth Cu3+ site, Cu3+ is bonded to six O2- atoms to form CuO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five CuO4 tetrahedra, edges with three MgO6 octahedra, and edges with three CuO6 octahedra. There are a spread of Cu–O bond distances ranging from 1.92–2.11 Å. In the tenth Cu3+ site, Cu3+ is bonded to four O2- atoms to form CuO4 tetrahedra that share corners with six MgO6 octahedra and corners with six CuO6 octahedra. The corner-sharing octahedra tilt angles range from 56–59°. There is three shorter (1.92 Å) and one longer (1.99 Å) Cu–O bond length. In the eleventh Cu3+ site, Cu3+ is bonded to six O2- atoms to form CuO6 octahedra that share corners with three equivalent MgO4 tetrahedra, corners with three equivalent CuO4 tetrahedra, edges with two MgO6 octahedra, and edges with four CuO6 octahedra. There is four shorter (1.96 Å) and two longer (2.03 Å) Cu–O bond length. In the twelfth Cu3+ site, Cu3+ is bonded to four O2- atoms to form CuO4 tetrahedra that share corners with three MgO6 octahedra and corners with nine CuO6 octahedra. The corner-sharing octahedra tilt angles range from 54–63°. There are a spread of Cu–O bond distances ranging from 1.89–2.00 Å. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded to two Mg2+ and two Cu3+ atoms to form a mixture of distorted corner and edge-sharing OMg2Cu2 trigonal pyramids. In the second O2- site, O2- is bonded to two Mg2+ and two equivalent Cu3+ atoms to form a mixture of distorted corner and edge-sharing OMg2Cu2 trigonal pyramids. In the third O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Cu3+ atoms. In the fourth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to four Cu3+ atoms. In the fifth O2- site, O2- is bonded to two Mg2+ and two Cu3+ atoms to form distorted OMg2Cu2 trigonal pyramids that share corners with three OMg2Cu2 trigonal pyramids and edges with two OMgCu3 trigonal pyramids. In the sixth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Cu3+ atoms. In the seventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Cu3+ atoms. In the eighth O2- site, O2- is bonded to one Mg2+ and three Cu3+ atoms to form distorted corner-sharing OMgCu3 trigonal pyramids. In the ninth O2- site, O2- is bonded to one Mg2+ and three Cu3+ atoms to form a mixture of distorted corner and edge-sharing OMgCu3 trigonal pyramids. In the tenth O2- site, O2- is bonded to two Mg2+ and two Cu3+ atoms to form a mixture of distorted corner and edge-sharing OMg2Cu2 trigonal pyramids. In the eleventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Cu3+ atoms. In the twelfth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Cu3+ atoms. In the thirteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Cu3+ atoms. In the fourteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Cu3+ atoms. In the fifteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Cu3+ atoms. In the sixteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Cu3+ atoms. In the seventeenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Cu3+ atoms. In the eighteenth O2- site, O2- is bonded to two Mg2+ and two Cu3+ atoms to form a mixture of distorted corner and edge-sharing OMg2Cu2 trigonal pyramids. In the nineteenth O2- site, O2- is bonded to two Mg2+ and two equivalent Cu3+ atoms to form distorted corner-sharing OMg2Cu2 trigonal pyramids. In the twentieth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Cu3+ atoms. In the twenty-first O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Cu3+ atoms. In the twenty-second O2- site, O2- is bonded in a rectangular see-saw-like geometry to four Cu3+ atoms. In the twenty-third O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Cu3+ atoms. In the twenty-fourth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Cu3+ atoms.