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DOE OSTI · 1321191

Materials Data on MgMn2O4 by Materials Project

Abstract

MgMn2O4 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 MnO6 octahedra. The corner-sharing octahedra tilt angles range from 54–60°. There are a spread of Mg–O bond distances ranging from 1.99–2.02 Å. 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 MnO4 tetrahedra, and edges with six MnO6 octahedra. There are four shorter (2.09 Å) and two longer (2.10 Å) Mg–O bond lengths. 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 MnO6 octahedra. The corner-sharing octahedra tilt angles range from 57–61°. There are a spread of Mg–O bond distances ranging from 2.02–2.05 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 MnO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with five MnO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.06–2.11 Å. In the fifth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six MnO4 tetrahedra, edges with two MgO6 octahedra, and edges with four equivalent MnO6 octahedra. There are four shorter (2.07 Å) and two longer (2.11 Å) Mg–O bond lengths. In the sixth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six MnO4 tetrahedra, edges with two MgO6 octahedra, and edges with four MnO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.06–2.14 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 MnO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with five MnO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.05–2.11 Å. In the eighth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six MnO4 tetrahedra, edges with two MgO6 octahedra, and edges with four MnO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.06–2.13 Å. There are twelve inequivalent Mn3+ sites. In the first Mn3+ site, Mn3+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with three MgO4 tetrahedra, corners with three MnO4 tetrahedra, edges with two equivalent MgO6 octahedra, and edges with four MnO6 octahedra. There are a spread of Mn–O bond distances ranging from 1.99–2.13 Å. In the second Mn3+ site, Mn3+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with three equivalent MgO4 tetrahedra, corners with three equivalent MnO4 tetrahedra, edges with two MgO6 octahedra, and edges with four MnO6 octahedra. There are a spread of Mn–O bond distances ranging from 1.98–2.10 Å. In the third Mn3+ site, Mn3+ is bonded to four O2- atoms to form MnO4 tetrahedra that share corners with six MgO6 octahedra and corners with six MnO6 octahedra. The corner-sharing octahedra tilt angles range from 58–61°. There are a spread of Mn–O bond distances ranging from 2.01–2.09 Å. In the fourth Mn3+ site, Mn3+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four MnO4 tetrahedra, edges with three MgO6 octahedra, and edges with three MnO6 octahedra. There are a spread of Mn–O bond distances ranging from 1.92–2.06 Å. In the fifth Mn3+ site, Mn3+ is bonded to four O2- atoms to form MnO4 tetrahedra that share corners with three MgO6 octahedra and corners with nine MnO6 octahedra. The corner-sharing octahedra tilt angles range from 55–61°. There are a spread of Mn–O bond distances ranging from 1.99–2.05 Å. In the sixth Mn3+ site, Mn3+ is bonded to four O2- atoms to form MnO4 tetrahedra that share corners with six MgO6 octahedra and corners with six MnO6 octahedra. The corner-sharing octahedra tilt angles range from 56–62°. There are two shorter (2.02 Å) and two longer (2.05 Å) Mn–O bond lengths. In the seventh Mn3+ site, Mn3+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with six MnO4 tetrahedra, edges with two equivalent MnO6 octahedra, and edges with four MgO6 octahedra. There are a spread of Mn–O bond distances ranging from 1.94–2.01 Å. In the eighth Mn3+ site, Mn3+ is bonded to four O2- atoms to form MnO4 tetrahedra that share corners with six MgO6 octahedra and corners with six MnO6 octahedra. The corner-sharing octahedra tilt angles range from 56–62°. There are a spread of Mn–O bond distances ranging from 2.02–2.06 Å. In the ninth Mn3+ site, Mn3+ is bonded to six O2- atoms to form MnO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with five MnO4 tetrahedra, edges with three MgO6 octahedra, and edges with three MnO6 octahedra. There are a spread of Mn–O bond distances ranging from 1.92–2.07 Å. In the tenth Mn3+ site, Mn3+ is bonded to four O2- atoms to form MnO4 tetrahedra that share corners with six MgO6 octahedra and corners with six MnO6 octahedra. The corner-sharing octahedra tilt angles range from 58–61°. There are a spread of Mn–O bond distances ranging from 2.01–2.10 Å. In the eleventh Mn3+ site, Mn3+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with three equivalent MgO4 tetrahedra, corners with three equivalent MnO4 tetrahedra, edges with two MgO6 octahedra, and edges with four MnO6 octahedra. There are a spread of Mn–O bond distances ranging from 1.98–2.08 Å. In the twelfth Mn3+ site, Mn3+ is bonded to four O2- atoms to form MnO4 tetrahedra that share corners with three MgO6 octahedra and corners with nine MnO6 octahedra. The corner-sharing octahedra tilt angles range from 57–62°. There are three shorter (2.05 Å) and one longer (2.07 Å) Mn–O bond lengths. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded to two Mg2+ and two Mn3+ atoms to form distorted OMg2Mn2 trigonal pyramids that share corners with two equivalent OMgMn3 tetrahedra, corners with seven OMn4 trigonal pyramids, and edges with two OMg2Mn2 trigonal pyramids. In the second O2- site, O2- is bonded to two Mg2+ and two equivalent Mn3+ atoms to form a mixture of distorted edge and corner-sharing OMg2Mn2 trigonal pyramids. In the third O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Mn3+ atoms. In the fourth O2- site, O2- is bonded in a rectangular see-saw-like geometry to four Mn3+ atoms. In the fifth O2- site, O2- is bonded to two Mg2+ and two Mn3+ atoms to form distorted OMg2Mn2 trigonal pyramids that share corners with five OMg2Mn2 trigonal pyramids and edges with three OMgMn3 trigonal pyramids. In the sixth O2- site, O2- is bonded to one Mg2+ and three Mn3+ atoms to form distorted OMgMn3 trigonal pyramids that share corners with nine OMg2Mn2 trigonal pyramids and edges with two OMgMn3 trigonal pyramids. In the seventh O2- site, O2- is bonded to one Mg2+ and three Mn3+ atoms to form distorted OMgMn3 trigonal pyramids that share corners with two equivalent OMg2Mn2 trigonal pyramids and edges with three OMgMn3 trigonal pyramids. In the eighth O2- site, O2- is bonded to one Mg2+ and three Mn3+ atoms to form distorted OMgMn3 trigonal pyramids that share corners with two equivalent OMgMn3 tetrahedra, corners with eight OMn4 trigonal pyramids, and edges with two equivalent OMgMn3 trigonal pyramids. In the ninth O2- site, O2- is bonded to one Mg2+ and three Mn3+ atoms to form a mixture of distorted edge and corner-sharing OMgMn3 trigonal pyramids. In the tenth O2- site, O2- is bonded to two Mg2+ and two Mn3+ atoms to form a mixture of distorted edge and corner-sharing OMg2Mn2 trigonal pyramids. In the eleventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Mn3+ atoms. In the twelfth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two Mn3+ atoms. In the thirteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Mn3+ atoms. In the fourteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Mn3+ atoms. In the fifteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Mn3+ atoms. In the sixteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Mn3+ atoms. In the seventeenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two Mn3+ atoms. In the eighteenth O2- site, O2- is bonded to two Mg2+ and two Mn3+ atoms to form a mixture of distorted edge and corner-sharing OMg2Mn2 trigonal pyramids. In the nineteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+ and two equivalent Mn3+ atoms. In the twentieth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Mn3+ atoms. In the twenty-first O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three Mn3+ atoms. In the twenty-second O2- site, O2- is bonded to four Mn3+ atoms to form distorted OMn4 trigonal pyramids that share corners with two equivalent OMgMn3 tetrahedra, corners with three OMg2Mn2 trigonal pyramids, edges with two equivalent OMgMn3 tetrahedra, and an edgeedge with one OMgMn3 trigonal pyramid. In the twenty-third O2- site, O2- is bonded to one Mg2+ and three Mn3+ atoms to form distorted OMgMn3 tetrahedra that share a cornercorner with one OMgMn3 tetrahedra, corners with four OMn4 trigonal pyramids, an edgeedge with one OMgMn3 tetrahedra, and edges with two OMn4 trigonal pyramids. In the twenty-fourth O2- site, O2- is bonded to one Mg2+ and three Mn3+ atoms to form distorted OMgMn3 trigonal pyramids that share corners with two equivalent OMg2Mn2 trigonal pyramids, edges with two equivalent OMgMn3 tetrahedra, and an edgeedge with one OMn4 trigonal pyramid.

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2020-05-02. Materials Data on MgMn2O4 by Materials Project. https://doi.org/10.17188/1321191

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