Materials Data on Mg3Fe(SiO4)2 by Materials Project

Mg3Fe(SiO4)2 is Hausmannite-derived structured and crystallizes in the orthorhombic Pmc2_1 space group. The structure is three-dimensional. there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with four equivalent MgO6 octahedra, corners with four equivalent FeO6 octahedra, corners with four SiO4 tetrahedra, edges with two equivalent MgO6 octahedra, and an edgeedge with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–62°. There are a spread of Mg–O bond distances ranging from 2.09–2.23 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with two equivalent FeO6 octahedra, corners with two SiO4 tetrahedra, an edgeedge with one FeO6 octahedra, edges with three MgO6 octahedra, and edges with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–65°. There are a spread of Mg–O bond distances ranging from 2.08–2.17 Å. Fe2+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with eight MgO6 octahedra, corners with four SiO4 tetrahedra, edges with two equivalent MgO6 octahedra, and an edgeedge with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–65°. There are a spread of Fe–O bond distances ranging from 2.11–2.30 Å. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent FeO6 octahedra, corners with four MgO6 octahedra, an edgeedge with one FeO6 octahedra, and edges with two equivalent MgO6 octahedra. The corner-sharing octahedra tilt angles range from 54–65°. There are a spread of Si–O bond distances ranging from 1.63–1.67 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent FeO6 octahedra, corners with four MgO6 octahedra, and edges with three MgO6 octahedra. The corner-sharing octahedra tilt angles range from 55–61°. There are a spread of Si–O bond distances ranging from 1.63–1.67 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Mg2+, one Fe2+, and one Si4+ atom. In the second O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+, one Fe2+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Mg2+, one Fe2+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to three Mg2+ and one Si4+ atom. In the fifth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two equivalent Mg2+, one Fe2+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Mg2+ and one Si4+ atom.