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DOE OSTI · 1297893

Materials Data on Mg5Co19O32 by Materials Project

Abstract

Mg5Co19O32 is Spinel-like structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are five inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to four O2- atoms to form MgO4 tetrahedra that share corners with twelve CoO6 octahedra. The corner-sharing octahedra tilt angles range from 59–60°. There is three shorter (1.96 Å) and one longer (1.97 Å) Mg–O bond length. In the second Mg2+ site, Mg2+ is bonded to four O2- atoms to form MgO4 tetrahedra that share corners with twelve CoO6 octahedra. The corner-sharing octahedra tilt angles range from 59–60°. All Mg–O bond lengths are 1.97 Å. In the third Mg2+ site, Mg2+ is bonded to four O2- atoms to form MgO4 tetrahedra that share corners with twelve CoO6 octahedra. The corner-sharing octahedra tilt angles range from 59–60°. There is one shorter (1.96 Å) and three longer (1.97 Å) Mg–O bond length. In the fourth Mg2+ site, Mg2+ is bonded to four O2- atoms to form MgO4 tetrahedra that share corners with twelve CoO6 octahedra. The corner-sharing octahedra tilt angles range from 59–60°. There is one shorter (1.96 Å) and three longer (1.97 Å) Mg–O bond length. In the fifth Mg2+ site, Mg2+ is bonded to four O2- atoms to form MgO4 tetrahedra that share corners with twelve CoO6 octahedra. The corner-sharing octahedra tilt angles range from 59–60°. All Mg–O bond lengths are 1.97 Å. There are eleven inequivalent Co+2.84+ sites. In the first Co+2.84+ site, Co+2.84+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with two equivalent CoO4 tetrahedra, corners with four MgO4 tetrahedra, and edges with six CoO6 octahedra. There is three shorter (1.93 Å) and three longer (1.94 Å) Co–O bond length. In the second Co+2.84+ site, Co+2.84+ is bonded to six equivalent O2- atoms to form CoO6 octahedra that share corners with six MgO4 tetrahedra and edges with six CoO6 octahedra. All Co–O bond lengths are 1.93 Å. In the third Co+2.84+ site, Co+2.84+ is bonded to four O2- atoms to form corner-sharing CoO4 tetrahedra. The corner-sharing octahedral tilt angles are 59°. There is one shorter (1.95 Å) and three longer (1.96 Å) Co–O bond length. In the fourth Co+2.84+ site, Co+2.84+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with two CoO4 tetrahedra, corners with four MgO4 tetrahedra, and edges with six CoO6 octahedra. There is four shorter (1.93 Å) and two longer (1.94 Å) Co–O bond length. In the fifth Co+2.84+ site, Co+2.84+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with three equivalent MgO4 tetrahedra, corners with three equivalent CoO4 tetrahedra, and edges with six CoO6 octahedra. There is three shorter (1.93 Å) and three longer (1.94 Å) Co–O bond length. In the sixth Co+2.84+ site, Co+2.84+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with three equivalent MgO4 tetrahedra, corners with three equivalent CoO4 tetrahedra, and edges with six CoO6 octahedra. There is three shorter (1.93 Å) and three longer (1.94 Å) Co–O bond length. In the seventh Co+2.84+ site, Co+2.84+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with three MgO4 tetrahedra, corners with three CoO4 tetrahedra, and edges with six CoO6 octahedra. There is three shorter (1.93 Å) and three longer (1.94 Å) Co–O bond length. In the eighth Co+2.84+ site, Co+2.84+ is bonded to four O2- atoms to form corner-sharing CoO4 tetrahedra. The corner-sharing octahedral tilt angles are 59°. All Co–O bond lengths are 1.96 Å. In the ninth Co+2.84+ site, Co+2.84+ is bonded to four O2- atoms to form corner-sharing CoO4 tetrahedra. The corner-sharing octahedra tilt angles range from 59–60°. There is one shorter (1.95 Å) and three longer (1.96 Å) Co–O bond length. In the tenth Co+2.84+ site, Co+2.84+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with three equivalent MgO4 tetrahedra, corners with three equivalent CoO4 tetrahedra, and edges with six CoO6 octahedra. There is three shorter (1.93 Å) and three longer (1.94 Å) Co–O bond length. In the eleventh Co+2.84+ site, Co+2.84+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with two equivalent CoO4 tetrahedra, corners with four MgO4 tetrahedra, and edges with six CoO6 octahedra. There is three shorter (1.93 Å) and three longer (1.94 Å) Co–O bond length. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded to four Co+2.84+ atoms to form distorted OCo4 trigonal pyramids that share corners with two equivalent OMgCo3 tetrahedra, corners with ten OCo4 trigonal pyramids, an edgeedge with one OMgCo3 tetrahedra, and edges with two equivalent OCo4 trigonal pyramids. In the second O2- site, O2- is bonded to one Mg2+ and three Co+2.84+ atoms to form a mixture of distorted edge and corner-sharing OMgCo3 trigonal pyramids. In the third O2- site, O2- is bonded to one Mg2+ and three equivalent Co+2.84+ atoms to form distorted OMgCo3 tetrahedra that share corners with three equivalent OMgCo3 tetrahedra, corners with nine OCo4 trigonal pyramids, and edges with three equivalent OMgCo3 trigonal pyramids. In the fourth O2- site, O2- is bonded to one Mg2+ and three Co+2.84+ atoms to form distorted OMgCo3 trigonal pyramids that share a cornercorner with one OMgCo3 tetrahedra, corners with eleven OCo4 trigonal pyramids, and edges with three OMgCo3 trigonal pyramids. In the fifth O2- site, O2- is bonded to one Mg2+ and three equivalent Co+2.84+ atoms to form distorted OMgCo3 tetrahedra that share corners with three equivalent OMgCo3 tetrahedra, corners with nine equivalent OMgCo3 trigonal pyramids, and edges with three equivalent OCo4 trigonal pyramids. In the sixth O2- site, O2- is bonded to four Co+2.84+ atoms to form distorted OCo4 trigonal pyramids that share corners with twelve OCo4 trigonal pyramids and edges with three equivalent OMgCo3 trigonal pyramids. In the seventh O2- site, O2- is bonded to one Mg2+ and three Co+2.84+ atoms to form distorted OMgCo3 trigonal pyramids that share corners with twelve OMgCo3 trigonal pyramids and edges with three OCo4 trigonal pyramids. In the eighth O2- site, O2- is bonded to four Co+2.84+ atoms to form distorted OCo4 trigonal pyramids that share corners with twelve OMgCo3 trigonal pyramids and edges with three OCo4 trigonal pyramids. In the ninth O2- site, O2- is bonded to four Co+2.84+ atoms to form distorted OCo4 trigonal pyramids that share corners with twelve OCo4 trigonal pyramids and edges with three equivalent OMgCo3 trigonal pyramids. In the tenth O2- site, O2- is bonded to four Co+2.84+ atoms to form a mixture of distorted edge and corner-sharing OCo4 trigonal pyramids. In the eleventh O2- site, O2- is bonded to one Mg2+ and three Co+2.84+ atoms to form distorted OMgCo3 trigonal pyramids that share a cornercorner with one OMgCo3 tetrahedra, corners with eleven OCo4 trigonal pyramids, and edges with three OMgCo3 trigonal pyramids. In the twelfth O2- site, O2- is bonded to one Mg2+ and three equivalent Co+2.84+ atoms to form distorted OMgCo3 trigonal pyramids that share corners with twelve OCo4 trigonal pyramids and edges with three equivalent OMgCo3 trigonal pyramids. In the thirteenth O2- site, O2- is bonded to four Co+2.84+ atoms to form distorted OCo4 trigonal pyramids that share corners with two equivalent OMgCo3 tetrahedra, corners with ten OCo4 trigonal pyramids, an edgeedge with one OMgCo3 tetrahedra, and edges with two equivalent OCo4 trigonal pyramids. In the fourteenth O2- site, O2- is bonded to one Mg2+ and three equivalent Co+2.84+ atoms to form a mixture of distorted edge and corner-sharing OMgCo3 tetrahedra.

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2020-05-02. Materials Data on Mg5Co19O32 by Materials Project. https://doi.org/10.17188/1297893

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