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DOE OSTI · 1704450

Materials Data on Mn5Cr4O12 by Materials Project

Abstract

Cr4Mn5O12 is Spinel-like structured and crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are five inequivalent Cr+3.50+ sites. In the first Cr+3.50+ site, Cr+3.50+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with six MnO4 tetrahedra, edges with two MnO6 octahedra, and edges with four CrO6 octahedra. There are a spread of Cr–O bond distances ranging from 2.01–2.08 Å. In the second Cr+3.50+ site, Cr+3.50+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with six MnO4 tetrahedra, edges with two equivalent CrO6 octahedra, and edges with four MnO6 octahedra. There are a spread of Cr–O bond distances ranging from 2.02–2.05 Å. In the third Cr+3.50+ site, Cr+3.50+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with six MnO4 tetrahedra, edges with two MnO6 octahedra, and edges with four CrO6 octahedra. There are a spread of Cr–O bond distances ranging from 2.02–2.07 Å. In the fourth Cr+3.50+ site, Cr+3.50+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with six MnO4 tetrahedra, edges with three CrO6 octahedra, and edges with three MnO6 octahedra. There are a spread of Cr–O bond distances ranging from 2.03–2.05 Å. In the fifth Cr+3.50+ site, Cr+3.50+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with six MnO4 tetrahedra, edges with two equivalent MnO6 octahedra, and edges with four CrO6 octahedra. There are a spread of Cr–O bond distances ranging from 2.03–2.05 Å. There are six inequivalent Mn2+ sites. In the first Mn2+ site, Mn2+ is bonded to four O2- atoms to form MnO4 tetrahedra that share corners with five MnO6 octahedra and corners with seven CrO6 octahedra. The corner-sharing octahedra tilt angles range from 56–62°. There are one shorter (2.05 Å) and three longer (2.08 Å) Mn–O bond lengths. In the second Mn2+ site, Mn2+ is bonded to four O2- atoms to form MnO4 tetrahedra that share corners with three MnO6 octahedra and corners with nine CrO6 octahedra. The corner-sharing octahedra tilt angles range from 56–64°. There are a spread of Mn–O bond distances ranging from 2.04–2.08 Å. In the third Mn2+ site, Mn2+ is bonded to four O2- atoms to form MnO4 tetrahedra that share corners with four MnO6 octahedra and corners with eight CrO6 octahedra. The corner-sharing octahedra tilt angles range from 55–64°. There are a spread of Mn–O bond distances ranging from 2.05–2.08 Å. In the fourth Mn2+ site, Mn2+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with six MnO4 tetrahedra, an edgeedge with one MnO6 octahedra, and edges with five CrO6 octahedra. There are a spread of Mn–O bond distances ranging from 1.95–2.16 Å. In the fifth Mn2+ site, Mn2+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with six MnO4 tetrahedra and edges with six CrO6 octahedra. There are a spread of Mn–O bond distances ranging from 1.99–2.16 Å. In the sixth Mn2+ site, Mn2+ 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 CrO6 octahedra. There are a spread of Mn–O bond distances ranging from 1.97–2.17 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded to three Cr+3.50+ and one Mn2+ atom to form a mixture of distorted corner and edge-sharing OMnCr3 trigonal pyramids. In the second O2- site, O2- is bonded to two Cr+3.50+ and two Mn2+ atoms to form distorted OMn2Cr2 trigonal pyramids that share corners with nine OMnCr3 trigonal pyramids and edges with two OMn3Cr trigonal pyramids. In the third O2- site, O2- is bonded to three Cr+3.50+ and one Mn2+ atom to form distorted OMnCr3 trigonal pyramids that share a cornercorner with one OMn2Cr2 tetrahedra, corners with eight OMnCr3 trigonal pyramids, an edgeedge with one OMn2Cr2 tetrahedra, and an edgeedge with one OMn2Cr2 trigonal pyramid. In the fourth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Cr+3.50+ and two Mn2+ atoms. In the fifth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Cr+3.50+ and two Mn2+ atoms. In the sixth O2- site, O2- is bonded to two Cr+3.50+ and two Mn2+ atoms to form distorted OMn2Cr2 tetrahedra that share corners with two equivalent OMn2Cr2 tetrahedra, corners with six OMnCr3 trigonal pyramids, and edges with two OMnCr3 trigonal pyramids. In the seventh O2- site, O2- is bonded to two Cr+3.50+ and two Mn2+ atoms to form distorted OMn2Cr2 trigonal pyramids that share corners with eight OMn2Cr2 trigonal pyramids and edges with two OMnCr3 trigonal pyramids. In the eighth O2- site, O2- is bonded to one Cr+3.50+ and three Mn2+ atoms to form distorted OMn3Cr trigonal pyramids that share corners with nine OMnCr3 trigonal pyramids and edges with two OMn2Cr2 trigonal pyramids. In the ninth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Cr+3.50+ and two Mn2+ atoms. In the tenth O2- site, O2- is bonded to two Cr+3.50+ and two Mn2+ atoms to form distorted OMn2Cr2 trigonal pyramids that share corners with two equivalent OMn2Cr2 tetrahedra, corners with seven OMnCr3 trigonal pyramids, and edges with two OMn2Cr2 trigonal pyramids. In the eleventh O2- site, O2- is bonded to one Cr+3.50+ and three Mn2+ atoms to form distorted OMn3Cr trigonal pyramids that share corners with nine OMn2Cr2 trigonal pyramids and edges with two OMn3Cr trigonal pyramids. In the twelfth O2- site, O2- is bonded to two Cr+3.50+ and two Mn2+ atoms to form distorted OMn2Cr2 trigonal pyramids that share a cornercorner with one OMn2Cr2 tetrahedra, corners with eight OMnCr3 trigonal pyramids, an edgeedge with one OMn2Cr2 tetrahedra, and an edgeedge with one OMnCr3 trigonal pyramid.

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2020-04-30. Materials Data on Mn5Cr4O12 by Materials Project. https://doi.org/10.17188/1704450

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