Materials Data on Fe7SiO10 by Materials Project

Abstract

Fe7SiO10 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are seven inequivalent Fe+2.29+ sites. In the first Fe+2.29+ site, Fe+2.29+ is bonded to six O2- atoms to form FeO6 octahedra that share a cornercorner with one FeO6 octahedra, corners with two equivalent FeO4 tetrahedra, corners with four equivalent SiO4 tetrahedra, and edges with six FeO6 octahedra. The corner-sharing octahedral tilt angles are 1°. There are a spread of Fe–O bond distances ranging from 2.02–2.27 Å. In the second Fe+2.29+ site, Fe+2.29+ is bonded to six O2- atoms to form FeO6 octahedra that share a cornercorner with one FeO6 octahedra, corners with two equivalent SiO4 tetrahedra, corners with four equivalent FeO4 tetrahedra, and edges with six FeO6 octahedra. The corner-sharing octahedral tilt angles are 4°. There are a spread of Fe–O bond distances ranging from 2.11–2.35 Å. In the third Fe+2.29+ site, Fe+2.29+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with four equivalent FeO6 octahedra, a cornercorner with one FeO4 tetrahedra, and edges with ten FeO6 octahedra. The corner-sharing octahedra tilt angles range from 3–10°. There are a spread of Fe–O bond distances ranging from 2.00–2.11 Å. In the fourth Fe+2.29+ site, Fe+2.29+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with four equivalent FeO6 octahedra, a cornercorner with one SiO4 tetrahedra, and edges with ten FeO6 octahedra. The corner-sharing octahedra tilt angles range from 3–16°. There are a spread of Fe–O bond distances ranging from 2.08–2.22 Å. In the fifth Fe+2.29+ site, Fe+2.29+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with five FeO6 octahedra, a cornercorner with one FeO4 tetrahedra, and edges with ten FeO6 octahedra. The corner-sharing octahedra tilt angles range from 1–10°. There are a spread of Fe–O bond distances ranging from 2.07–2.35 Å. In the sixth Fe+2.29+ site, Fe+2.29+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with five FeO6 octahedra, a cornercorner with one SiO4 tetrahedra, and edges with ten FeO6 octahedra. The corner-sharing octahedra tilt angles range from 3–16°. There are a spread of Fe–O bond distances ranging from 2.10–2.28 Å. In the seventh Fe+2.29+ site, Fe+2.29+ is bonded to four O2- atoms to form FeO4 tetrahedra that share corners with eight FeO6 octahedra and corners with two equivalent FeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 54–61°. There are a spread of Fe–O bond distances ranging from 1.89–1.91 Å. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with eight FeO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–60°. There are a spread of Si–O bond distances ranging from 1.63–1.75 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a trigonal planar geometry to one Fe+2.29+ and two equivalent Si4+ atoms. In the second O2- site, O2- is bonded in a trigonal planar geometry to three Fe+2.29+ atoms. In the third O2- site, O2- is bonded to five Fe+2.29+ atoms to form OFe5 square pyramids that share corners with four equivalent OFe6 octahedra, a cornercorner with one OFe4 trigonal pyramid, edges with four OFe6 octahedra, and edges with four OFe5 square pyramids. The corner-sharing octahedra tilt angles range from 6–8°. In the fourth O2- site, O2- is bonded to five Fe+2.29+ atoms to form OFe5 square pyramids that share corners with four equivalent OFe6 octahedra, corners with four OFe4 trigonal pyramids, edges with four OFe6 octahedra, and edges with four OFe5 square pyramids. The corner-sharing octahedral tilt angles are 5°. In the fifth O2- site, O2- is bonded to six Fe+2.29+ atoms to form OFe6 octahedra that share corners with four equivalent OFe5 square pyramids, a cornercorner with one OFe4 trigonal pyramid, edges with four OFe6 octahedra, and edges with four OFe5 square pyramids. In the sixth O2- site, O2- is bonded to six Fe+2.29+ atoms to form OFe6 octahedra that share corners with four equivalent OFe5 square pyramids, edges with four OFe6 octahedra, edges with four OFe5 square pyramids, and edges with four OFe4 trigonal pyramids. In the seventh O2- site, O2- is bonded to four Fe+2.29+ atoms to form distorted OFe4 trigonal pyramids that share corners with three OFe5 square pyramids, corners with five OFe4 trigonal pyramids, edges with two equivalent OFe6 octahedra, and an edgeedge with one OFe4 trigonal pyramid. In the eighth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Fe+2.29+ and one Si4+ atom. In the ninth O2- site, O2- is bonded to four Fe+2.29+ atoms to form distorted OFe4 trigonal pyramids that share a cornercorner with one OFe6 octahedra, corners with two equivalent OFe5 square pyramids, corners with five OFe4 trigonal pyramids, edges with two equivalent OFe6 octahedra, and an edgeedge with one OFe4 trigonal pyramid. The corner-sharing octahedral tilt angles are 4°. In the tenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Fe+2.29+ and one Si4+ atom.