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Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
NaFe9B3Si6H3O31 crystallizes in the trigonal R3m space group. The structure is three-dimensional. Na1+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Na–O bond distances ranging from 2.67–2.89 Å. There are two inequivalent Fe+2.78+ sites. In the first Fe+2.78+ site, Fe+2.78+ is bonded to six O2- atoms to form FeO6 octahedra that share a cornercorner with one FeO6 octahedra, corners with three equivalent SiO4 tetrahedra, and edges with three FeO6 octahedra. The corner-sharing octahedral tilt angles are 57°. There are a spread of Fe–O bond distances ranging from 2.03–2.15 Å. In the second Fe+2.78+ site, Fe+2.78+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent SiO4 tetrahedra and edges with four FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.99–2.10 Å. B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.38 Å) and one longer (1.41 Å) B–O bond length. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four FeO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 46–57°. There are a spread of Si–O bond distances ranging from 1.62–1.66 Å. H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to three Fe+2.78+ and one H1+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Fe+2.78+ and one B3+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two Fe+2.78+ and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+ and two equivalent Si4+ atoms. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Fe+2.78+ and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, two equivalent Fe+2.78+, and one B3+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Na1+ and two equivalent Si4+ atoms. In the eighth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to three equivalent Fe+2.78+ atoms.