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DOE OSTI · 1281115

Materials Data on Fe3(GeO4)2 by Materials Project

Abstract

Fe3(GeO4)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are three inequivalent Fe+2.67+ sites. In the first Fe+2.67+ site, Fe+2.67+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six GeO4 tetrahedra and edges with four FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 2.09–2.25 Å. In the second Fe+2.67+ site, Fe+2.67+ is bonded to six O2- atoms to form FeO6 octahedra that share a cornercorner with one FeO6 octahedra, corners with four GeO4 tetrahedra, and edges with five FeO6 octahedra. The corner-sharing octahedral tilt angles are 20°. There are a spread of Fe–O bond distances ranging from 2.00–2.21 Å. In the third Fe+2.67+ site, Fe+2.67+ is bonded to six O2- atoms to form FeO6 octahedra that share a cornercorner with one FeO6 octahedra, corners with five GeO4 tetrahedra, and edges with four FeO6 octahedra. The corner-sharing octahedral tilt angles are 20°. There are a spread of Fe–O bond distances ranging from 1.99–2.09 Å. There are two inequivalent Ge4+ sites. In the first Ge4+ site, Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share corners with seven FeO6 octahedra and a cornercorner with one GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 42–63°. There are a spread of Ge–O bond distances ranging from 1.75–1.83 Å. In the second Ge4+ site, Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share corners with eight FeO6 octahedra and a cornercorner with one GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 51–61°. There are a spread of Ge–O bond distances ranging from 1.76–1.85 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two Fe+2.67+ and one Ge4+ atom. In the second O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Fe+2.67+ and one Ge4+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two Fe+2.67+ and one Ge4+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Fe+2.67+ and one Ge4+ atom. In the fifth O2- site, O2- is bonded in a trigonal planar geometry to one Fe+2.67+ and two Ge4+ atoms. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Fe+2.67+ and one Ge4+ atom. In the seventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to four Fe+2.67+ atoms. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Fe+2.67+ and one Ge4+ atom.

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2020-08-03. Materials Data on Fe3(GeO4)2 by Materials Project. https://doi.org/10.17188/1281115

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