Materials Data on CaMgSiO4 by Materials Project
CaMgSiO4 is Ilmenite-derived structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Ca2+ is bonded to six O2- atoms to form distorted CaO6 octahedra that share corners with four equivalent CaO6 octahedra, corners with four equivalent MgO6 octahedra, corners with four equivalent SiO4 tetrahedra, edges with two equivalent MgO6 octahedra, and an edgeedge with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–64°. There are a spread of Ca–O bond distances ranging from 2.31–2.51 Å. Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with four equivalent CaO6 octahedra, corners with two equivalent SiO4 tetrahedra, edges with two equivalent CaO6 octahedra, edges with two equivalent MgO6 octahedra, and edges with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–64°. There are a spread of Mg–O bond distances ranging from 2.10–2.21 Å. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent MgO6 octahedra, corners with four equivalent CaO6 octahedra, an edgeedge with one CaO6 octahedra, and edges with two equivalent MgO6 octahedra. The corner-sharing octahedra tilt angles range from 50–65°. There are a spread of Si–O bond distances ranging from 1.63–1.67 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two equivalent Ca2+, one Mg2+, and one Si4+ atom. In the second O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Ca2+, two equivalent Mg2+, and one Si4+ atom. In the third O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Ca2+, two equivalent Mg2+, and one Si4+ atom.