Materials Data on Fe5SiO8 by Materials Project

Fe5SiO8 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are five inequivalent Fe+2.40+ sites. In the first Fe+2.40+ site, Fe+2.40+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with three equivalent FeO4 tetrahedra, corners with three equivalent SiO4 tetrahedra, and edges with six FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 2.08–2.24 Å. In the second Fe+2.40+ site, Fe+2.40+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with ten FeO6 octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 51–71°. There are a spread of Fe–O bond distances ranging from 1.88–1.95 Å. In the third Fe+2.40+ site, Fe+2.40+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent FeO6 octahedra, corners with two equivalent FeO4 tetrahedra, corners with two equivalent SiO4 tetrahedra, and edges with seven FeO6 octahedra. The corner-sharing octahedra tilt angles range from 11–13°. There are a spread of Fe–O bond distances ranging from 2.01–2.17 Å. In the fourth Fe+2.40+ site, Fe+2.40+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with three equivalent FeO4 tetrahedra, corners with three equivalent SiO4 tetrahedra, and edges with six FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 2.10–2.27 Å. In the fifth Fe+2.40+ site, Fe+2.40+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent FeO6 octahedra, corners with two equivalent FeO4 tetrahedra, corners with two equivalent SiO4 tetrahedra, and edges with seven FeO6 octahedra. The corner-sharing octahedra tilt angles range from 11–13°. There are a spread of Fe–O bond distances ranging from 2.09–2.28 Å. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with ten FeO6 octahedra and a cornercorner with one FeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 51–57°. There are a spread of Si–O bond distances ranging from 1.66–1.68 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to four Fe+2.40+ atoms. In the second O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Fe+2.40+ and one Si4+ atom. In the third O2- site, O2- is bonded in a rectangular see-saw-like geometry to four Fe+2.40+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Fe+2.40+ and one Si4+ atom. In the fifth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Fe+2.40+ and one Si4+ atom. In the sixth O2- site, O2- is bonded in a rectangular see-saw-like geometry to four Fe+2.40+ atoms. In the seventh O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Fe+2.40+ and one Si4+ atom. In the eighth O2- site, O2- is bonded to five Fe+2.40+ atoms to form edge-sharing OFe5 square pyramids.