Materials Data on BaYFeCuO5 by Materials Project

Abstract

YBaCuFeO5 crystallizes in the tetragonal P4mm space group. The structure is three-dimensional. Ba2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are four shorter (2.79 Å) and four longer (2.95 Å) Ba–O bond lengths. Y3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.38 Å) and four longer (2.45 Å) Y–O bond lengths. Fe3+ is bonded to five O2- atoms to form distorted FeO5 trigonal bipyramids that share a cornercorner with one CuO5 square pyramid and corners with four equivalent FeO5 trigonal bipyramids. There is one shorter (1.87 Å) and four longer (2.03 Å) Fe–O bond length. Cu2+ is bonded to five O2- atoms to form CuO5 square pyramids that share corners with four equivalent CuO5 square pyramids and a cornercorner with one FeO5 trigonal bipyramid. There are four shorter (1.96 Å) and one longer (2.50 Å) Cu–O bond lengths. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Y3+ and two equivalent Fe3+ atoms to form distorted OY2Fe2 tetrahedra that share corners with two equivalent OBa4FeCu octahedra, corners with four equivalent OY2Fe2 tetrahedra, and edges with four equivalent OY2Fe2 tetrahedra. The corner-sharing octahedral tilt angles are 74°. In the second O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Ba2+, two equivalent Y3+, and two equivalent Cu2+ atoms. In the third O2- site, O2- is bonded to four equivalent Ba2+, one Fe3+, and one Cu2+ atom to form distorted OBa4FeCu octahedra that share corners with four equivalent OBa4FeCu octahedra, corners with four equivalent OY2Fe2 tetrahedra, and edges with four equivalent OBa4FeCu octahedra. The corner-sharing octahedral tilt angles are 19°.