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DOE OSTI · 1672749

Materials Data on MgMn3O6 by Materials Project

Abstract

MgMn3O6 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. Mg2+ is bonded to six O2- atoms to form distorted MgO6 octahedra that share corners with five MnO6 octahedra, edges with two equivalent MgO6 octahedra, edges with five MnO6 octahedra, and a faceface with one MnO6 octahedra. The corner-sharing octahedra tilt angles range from 11–40°. There are a spread of Mg–O bond distances ranging from 1.96–2.24 Å. There are three inequivalent Mn+3.33+ sites. In the first Mn+3.33+ site, Mn+3.33+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with eight MnO6 octahedra, edges with two equivalent MnO6 octahedra, and a faceface with one MgO6 octahedra. The corner-sharing octahedra tilt angles range from 40–54°. There are a spread of Mn–O bond distances ranging from 1.93–2.20 Å. In the second Mn+3.33+ site, Mn+3.33+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with four equivalent MnO6 octahedra, edges with four equivalent MgO6 octahedra, and edges with four MnO6 octahedra. The corner-sharing octahedra tilt angles range from 49–54°. There are a spread of Mn–O bond distances ranging from 1.95–2.11 Å. In the third Mn+3.33+ site, Mn+3.33+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with three equivalent MgO6 octahedra, corners with four equivalent MnO6 octahedra, an edgeedge with one MgO6 octahedra, and edges with four MnO6 octahedra. The corner-sharing octahedra tilt angles range from 11–52°. There are a spread of Mn–O bond distances ranging from 1.92–2.19 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to three Mn+3.33+ atoms. In the second O2- site, O2- is bonded to two equivalent Mg2+ and three Mn+3.33+ atoms to form distorted OMg2Mn3 trigonal bipyramids that share corners with three equivalent OMg2Mn3 square pyramids, corners with two equivalent OMgMn3 trigonal pyramids, an edgeedge with one OMg2Mn3 square pyramid, edges with two equivalent OMg2Mn3 trigonal bipyramids, and edges with four OMgMn3 trigonal pyramids. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to three Mn+3.33+ atoms. In the fourth O2- site, O2- is bonded to one Mg2+ and three Mn+3.33+ atoms to form OMgMn3 trigonal pyramids that share corners with two equivalent OMg2Mn3 trigonal bipyramids, corners with five OMgMn3 trigonal pyramids, edges with two equivalent OMg2Mn3 square pyramids, edges with two equivalent OMg2Mn3 trigonal bipyramids, and an edgeedge with one OMgMn3 trigonal pyramid. In the fifth O2- site, O2- is bonded to two equivalent Mg2+ and three Mn+3.33+ atoms to form OMg2Mn3 square pyramids that share corners with three equivalent OMg2Mn3 trigonal bipyramids, corners with two equivalent OMgMn3 trigonal pyramids, edges with two equivalent OMg2Mn3 square pyramids, an edgeedge with one OMg2Mn3 trigonal bipyramid, and edges with four OMgMn3 trigonal pyramids. In the sixth O2- site, O2- is bonded to one Mg2+ and three Mn+3.33+ atoms to form distorted OMgMn3 trigonal pyramids that share corners with two equivalent OMg2Mn3 square pyramids, corners with five OMgMn3 trigonal pyramids, edges with two equivalent OMg2Mn3 square pyramids, edges with two equivalent OMg2Mn3 trigonal bipyramids, and an edgeedge with one OMgMn3 trigonal pyramid.

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2020-05-02. Materials Data on MgMn3O6 by Materials Project. https://doi.org/10.17188/1672749

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