Materials Data on MgSiO3 by Materials Project

Abstract

MgSiO3 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Mg2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Mg–O bond distances ranging from 2.05–2.30 Å. Si4+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing SiO6 octahedra. The corner-sharing octahedral tilt angles are 43°. There is two shorter (1.81 Å) and four longer (1.82 Å) Si–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to three equivalent Mg2+ and two equivalent Si4+ atoms. In the second O2- site, O2- is bonded to two equivalent Mg2+ and two equivalent Si4+ atoms to form distorted corner-sharing OMg2Si2 tetrahedra.