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DOE OSTI · 1321358

Materials Data on Mg(CoO2)2 by Materials Project

Abstract

MgCo2O4 is Spinel-like structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are six 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 CoO6 octahedra. The corner-sharing octahedra tilt angles range from 57–61°. There are a spread of Mg–O bond distances ranging from 1.94–2.05 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six CoO4 tetrahedra, edges with two MgO6 octahedra, and edges with four CoO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.04–2.08 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four CoO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with five CoO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.00–2.10 Å. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six CoO4 tetrahedra, edges with two MgO6 octahedra, and edges with four CoO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.03–2.08 Å. In the fifth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six CoO4 tetrahedra, edges with two MgO6 octahedra, and edges with four CoO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.03–2.08 Å. In the sixth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five CoO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with five CoO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.02–2.06 Å. There are twelve inequivalent Co3+ sites. In the first Co3+ site, Co3+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four CoO4 tetrahedra, edges with three MgO6 octahedra, and edges with three CoO6 octahedra. There are a spread of Co–O bond distances ranging from 1.91–1.98 Å. In the second Co3+ site, Co3+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with six MgO6 octahedra and corners with six CoO6 octahedra. The corner-sharing octahedra tilt angles range from 54–60°. There are a spread of Co–O bond distances ranging from 1.85–1.94 Å. In the third Co3+ site, Co3+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with three equivalent MgO4 tetrahedra, corners with three equivalent CoO4 tetrahedra, edges with two MgO6 octahedra, and edges with four CoO6 octahedra. There are a spread of Co–O bond distances ranging from 1.89–1.98 Å. In the fourth Co3+ site, Co3+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four CoO4 tetrahedra, edges with three MgO6 octahedra, and edges with three CoO6 octahedra. There are a spread of Co–O bond distances ranging from 1.91–1.98 Å. In the fifth Co3+ site, Co3+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with six CoO4 tetrahedra, edges with two equivalent CoO6 octahedra, and edges with four MgO6 octahedra. There are a spread of Co–O bond distances ranging from 1.92–1.97 Å. In the sixth Co3+ site, Co3+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with six MgO6 octahedra and corners with six CoO6 octahedra. The corner-sharing octahedra tilt angles range from 54–60°. There are a spread of Co–O bond distances ranging from 1.85–1.93 Å. In the seventh Co3+ site, Co3+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with six CoO4 tetrahedra, edges with two equivalent CoO6 octahedra, and edges with four MgO6 octahedra. There is two shorter (1.93 Å) and four longer (1.96 Å) Co–O bond length. In the eighth Co3+ site, Co3+ is bonded to six O2- atoms to form CoO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five CoO4 tetrahedra, edges with three MgO6 octahedra, and edges with three CoO6 octahedra. There are a spread of Co–O bond distances ranging from 1.92–1.98 Å. In the ninth Co3+ site, Co3+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with six MgO6 octahedra and corners with six CoO6 octahedra. The corner-sharing octahedra tilt angles range from 55–60°. There is two shorter (1.85 Å) and two longer (1.94 Å) Co–O bond length. In the tenth Co3+ site, Co3+ is bonded to six O2- atoms to form CoO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five CoO4 tetrahedra, edges with three MgO6 octahedra, and edges with three CoO6 octahedra. There are a spread of Co–O bond distances ranging from 1.91–1.99 Å. In the eleventh Co3+ site, Co3+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with six MgO6 octahedra and corners with six CoO6 octahedra. The corner-sharing octahedra tilt angles range from 55–60°. There is two shorter (1.86 Å) and two longer (1.94 Å) Co–O bond length. In the twelfth Co3+ site, Co3+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with three MgO6 octahedra and corners with nine CoO6 octahedra. The corner-sharing octahedra tilt angles range from 56–62°. There are a spread of Co–O bond distances ranging from 1.89–1.97 Å. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two Co3+ atoms. In the second O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Co3+ atoms. In the third O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Co3+ atoms. In the fourth O2- site, O2- is bonded to one Mg2+ and three Co3+ atoms to form distorted corner-sharing OMgCo3 trigonal pyramids. In the fifth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Co3+ atoms. In the sixth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Co3+ atoms. In the seventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Co3+ atoms. In the eighth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Co3+ atoms. In the ninth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Co3+ atoms. In the tenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Co3+ atoms. In the eleventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Co3+ atoms. In the twelfth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Co3+ atoms. In the thirteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Co3+ atoms. In the fourteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Co3+ atoms. In the fifteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Co3+ atoms. In the sixteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Co3+ atoms. In the seventeenth O2- site, O2- is bonded to two Mg2+ and two Co3+ atoms to form distorted corner-sharing OMg2Co2 trigonal pyramids. In the eighteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Co3+ atoms. In the nineteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Co3+ atoms. In the twentieth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two Co3+ atoms. In the twenty-first O2- site, O2- is bonded to four Co3+ atoms to form distorted corner-sharing OCo4 trigonal pyramids. In the twenty-second O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Co3+ atoms. In the twenty-third O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Co3+ atoms. In the twenty-fourth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Co3+ atoms.

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2020-04-29. Materials Data on Mg(CoO2)2 by Materials Project. https://doi.org/10.17188/1321358

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