Materials Data on Fe2SiO4 by Materials Project

Fe2SiO4 crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. there are two inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share corners with six equivalent SiO6 octahedra, edges with two equivalent SiO6 octahedra, and edges with six FeO6 octahedra. The corner-sharing octahedra tilt angles range from 4–14°. There are two shorter (2.05 Å) and four longer (2.45 Å) Fe–O bond lengths. In the second Fe2+ site, Fe2+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share edges with four equivalent SiO6 octahedra and edges with six FeO6 octahedra. There are two shorter (2.04 Å) and four longer (2.11 Å) Fe–O bond lengths. Si4+ is bonded to six O2- atoms to form SiO6 octahedra that share corners with six equivalent FeO6 octahedra, edges with two equivalent SiO6 octahedra, and edges with six FeO6 octahedra. The corner-sharing octahedra tilt angles range from 4–14°. There is two shorter (1.79 Å) and four longer (1.88 Å) Si–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Fe2+ and one Si4+ atom. In the second O2- site, O2- is bonded in a 5-coordinate geometry to three Fe2+ and two equivalent Si4+ atoms.