Materials Data on Sr3Ca(FeO3)4 by Materials Project

Abstract

Sr3Ca(FeO3)4 is (Cubic) Perovskite-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are three inequivalent Sr sites. In the first Sr site, Sr is bonded to twelve O atoms to form SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with two equivalent CaO12 cuboctahedra, faces with four equivalent SrO12 cuboctahedra, and faces with eight equivalent FeO6 octahedra. There are four shorter (2.75 Å) and eight longer (2.76 Å) Sr–O bond lengths. In the second Sr site, Sr is bonded to twelve O atoms to form SrO12 cuboctahedra that share corners with four equivalent SrO12 cuboctahedra, corners with eight equivalent CaO12 cuboctahedra, faces with six SrO12 cuboctahedra, and faces with eight equivalent FeO6 octahedra. There are four shorter (2.75 Å) and eight longer (2.78 Å) Sr–O bond lengths. In the third Sr site, Sr is bonded to twelve O atoms to form SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with two equivalent SrO12 cuboctahedra, faces with four equivalent CaO12 cuboctahedra, and faces with eight equivalent FeO6 octahedra. All Sr–O bond lengths are 2.75 Å. Ca is bonded to twelve O atoms to form CaO12 cuboctahedra that share corners with four equivalent CaO12 cuboctahedra, corners with eight equivalent SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, and faces with eight equivalent FeO6 octahedra. There are eight shorter (2.72 Å) and four longer (2.75 Å) Ca–O bond lengths. Fe is bonded to six O atoms to form FeO6 octahedra that share corners with six equivalent FeO6 octahedra, faces with two equivalent CaO12 cuboctahedra, and faces with six SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of Fe–O bond distances ranging from 1.93–1.96 Å. There are three inequivalent O sites. In the first O site, O is bonded to three Sr, one Ca, and two equivalent Fe atoms to form a mixture of distorted corner, edge, and face-sharing OSr3CaFe2 octahedra. The corner-sharing octahedra tilt angles range from 0–61°. In the second O site, O is bonded to four Sr and two equivalent Fe atoms to form distorted OSr4Fe2 octahedra that share corners with twenty OSr3CaFe2 octahedra, edges with four equivalent OSr4Fe2 octahedra, and faces with eight equivalent OSr3CaFe2 octahedra. The corner-sharing octahedra tilt angles range from 0–60°. In the third O site, O is bonded in a distorted linear geometry to two equivalent Sr, two equivalent Ca, and two equivalent Fe atoms.