Materials Data on Ca3MgFe2(CO3)6 by Materials Project

Abstract

Ca3MgFe2(CO3)6 is Calcite-derived structured and crystallizes in the trigonal P-3 space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to six equivalent O2- atoms to form CaO6 octahedra that share corners with six equivalent FeO6 octahedra. The corner-sharing octahedral tilt angles are 61°. All Ca–O bond lengths are 2.39 Å. In the second Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with three equivalent MgO6 octahedra and corners with three equivalent FeO6 octahedra. The corner-sharing octahedral tilt angles are 61°. There are three shorter (2.39 Å) and three longer (2.41 Å) Ca–O bond lengths. Mg2+ is bonded to six equivalent O2- atoms to form MgO6 octahedra that share corners with six equivalent CaO6 octahedra. The corner-sharing octahedral tilt angles are 61°. All Mg–O bond lengths are 2.13 Å. Fe2+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six CaO6 octahedra. The corner-sharing octahedral tilt angles are 61°. All Fe–O bond lengths are 2.15 Å. There are three inequivalent C4+ sites. In the first C4+ site, C4+ is bonded in a trigonal planar geometry to three equivalent O2- atoms. All C–O bond lengths are 1.30 Å. In the second C4+ site, C4+ is bonded in a trigonal planar geometry to three equivalent O2- atoms. All C–O bond lengths are 1.30 Å. In the third C4+ site, C4+ is bonded in a trigonal planar geometry to three equivalent O2- atoms. All C–O bond lengths are 1.30 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ca2+, one Mg2+, and one C4+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ca2+, one Fe2+, and one C4+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ca2+, one Fe2+, and one C4+ atom.