Materials Data on FeCo3 by Materials Project

Abstract

FeCo3 is alpha La-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Fe is bonded to four equivalent Fe and eight equivalent Co atoms to form FeFe4Co8 cuboctahedra that share corners with four equivalent FeFe4Co8 cuboctahedra, corners with eight equivalent CoCo12 cuboctahedra, edges with twenty-four CoFe4Co8 cuboctahedra, faces with eight equivalent FeFe4Co8 cuboctahedra, and faces with ten CoFe4Co8 cuboctahedra. All Fe–Fe bond lengths are 2.47 Å. All Fe–Co bond lengths are 2.50 Å. There are two inequivalent Co sites. In the first Co site, Co is bonded to four equivalent Fe and eight Co atoms to form CoFe4Co8 cuboctahedra that share corners with twelve equivalent CoFe4Co8 cuboctahedra, edges with eight equivalent FeFe4Co8 cuboctahedra, edges with sixteen CoFe4Co8 cuboctahedra, faces with four equivalent FeFe4Co8 cuboctahedra, and faces with fourteen CoFe4Co8 cuboctahedra. There are four shorter (2.46 Å) and four longer (2.47 Å) Co–Co bond lengths. In the second Co site, Co is bonded to twelve Co atoms to form CoCo12 cuboctahedra that share corners with four equivalent CoCo12 cuboctahedra, corners with eight equivalent FeFe4Co8 cuboctahedra, edges with eight equivalent FeFe4Co8 cuboctahedra, edges with sixteen equivalent CoFe4Co8 cuboctahedra, faces with two equivalent FeFe4Co8 cuboctahedra, and faces with sixteen CoFe4Co8 cuboctahedra. All Co–Co bond lengths are 2.47 Å.