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DOE OSTI · 1740343

Materials Data on KMgMn2AlGe3(O5F)2 by Materials Project

Abstract

KMgMn2AlGe3(O5F)2 crystallizes in the triclinic P1 space group. The structure is three-dimensional. K1+ is bonded to six O2- atoms to form distorted KO6 octahedra that share corners with three equivalent AlO4 tetrahedra and corners with nine GeO4 tetrahedra. There are a spread of K–O bond distances ranging from 2.77–3.10 Å. Mg2+ is bonded to four O2- and two F1- atoms to form MgO4F2 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with three GeO4 tetrahedra, and edges with six MnO4F2 octahedra. There are a spread of Mg–O bond distances ranging from 2.05–2.15 Å. There are one shorter (2.01 Å) and one longer (2.05 Å) Mg–F bond lengths. There are two inequivalent Mn2+ sites. In the first Mn2+ site, Mn2+ is bonded to four O2- and two F1- atoms to form MnO4F2 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with three GeO4 tetrahedra, edges with three equivalent MgO4F2 octahedra, and edges with three equivalent MnO4F2 octahedra. There are a spread of Mn–O bond distances ranging from 2.12–2.25 Å. There are one shorter (2.17 Å) and one longer (2.26 Å) Mn–F bond lengths. In the second Mn2+ site, Mn2+ is bonded to four O2- and two F1- atoms to form MnO4F2 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with three GeO4 tetrahedra, edges with three equivalent MgO4F2 octahedra, and edges with three equivalent MnO4F2 octahedra. There are a spread of Mn–O bond distances ranging from 2.12–2.27 Å. There are one shorter (2.16 Å) and one longer (2.22 Å) Mn–F bond lengths. Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share a cornercorner with one MgO4F2 octahedra, corners with two MnO4F2 octahedra, corners with three equivalent KO6 octahedra, and corners with three equivalent GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 57–68°. There is three shorter (1.77 Å) and one longer (1.79 Å) Al–O bond length. There are three inequivalent Ge4+ sites. In the first Ge4+ site, Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share a cornercorner with one MgO4F2 octahedra, corners with two MnO4F2 octahedra, corners with three equivalent KO6 octahedra, and corners with three equivalent AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 58–69°. There is three shorter (1.76 Å) and one longer (1.81 Å) Ge–O bond length. In the second Ge4+ site, Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share a cornercorner with one MgO4F2 octahedra, corners with two MnO4F2 octahedra, corners with three equivalent KO6 octahedra, and corners with three equivalent GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–67°. There is one shorter (1.75 Å) and three longer (1.79 Å) Ge–O bond length. In the third Ge4+ site, Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share a cornercorner with one MgO4F2 octahedra, corners with two MnO4F2 octahedra, corners with three equivalent KO6 octahedra, and corners with three equivalent GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 55–67°. There are a spread of Ge–O bond distances ranging from 1.75–1.79 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one K1+, one Al3+, and one Ge4+ atom. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one K1+ and two Ge4+ atoms. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one K1+, one Al3+, and one Ge4+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one K1+, one Al3+, and one Ge4+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one K1+ and two Ge4+ atoms. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one K1+ and two Ge4+ atoms. In the seventh O2- site, O2- is bonded to one Mg2+, two Mn2+, and one Al3+ atom to form distorted corner-sharing OMgMn2Al tetrahedra. In the eighth O2- site, O2- is bonded to one Mg2+, two Mn2+, and one Ge4+ atom to form distorted corner-sharing OMgMn2Ge tetrahedra. In the ninth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+, two Mn2+, and one Ge4+ atom. In the tenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+, two Mn2+, and one Ge4+ atom. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted trigonal non-coplanar geometry to one Mg2+ and two Mn2+ atoms. In the second F1- site, F1- is bonded in a 3-coordinate geometry to one Mg2+ and two Mn2+ atoms.

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2020-06-05. Materials Data on KMgMn2AlGe3(O5F)2 by Materials Project. https://doi.org/10.17188/1740343

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