Materials Data on Ca3AlFe(SiO4)3 by Materials Project

Abstract

Ca3FeAl(SiO4)3 crystallizes in the cubic Ia-3 space group. The structure is three-dimensional. Ca2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.36–2.53 Å. Fe3+ is bonded to six equivalent O2- atoms to form FeO6 octahedra that share corners with six equivalent SiO4 tetrahedra. All Fe–O bond lengths are 2.03 Å. Al3+ is bonded to six equivalent O2- atoms to form AlO6 octahedra that share corners with six equivalent SiO4 tetrahedra. All Al–O bond lengths are 1.96 Å. Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent FeO6 octahedra and corners with two equivalent AlO6 octahedra. The corner-sharing octahedra tilt angles range from 44–47°. There is two shorter (1.66 Å) and two longer (1.67 Å) Si–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ca2+, one Al3+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ca2+, one Fe3+, and one Si4+ atom.