Materials Data on BaFeCuF7 by Materials Project
BaFeCuF7 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded to twelve F1- atoms to form distorted BaF12 cuboctahedra that share corners with two equivalent BaF12 cuboctahedra, corners with two equivalent FeF6 octahedra, corners with four equivalent CuF6 octahedra, edges with four equivalent BaF12 cuboctahedra, edges with two equivalent FeF6 octahedra, edges with two equivalent CuF6 octahedra, and faces with two equivalent FeF6 octahedra. The corner-sharing octahedra tilt angles range from 49–53°. There are a spread of Ba–F bond distances ranging from 2.71–3.15 Å. In the second Ba2+ site, Ba2+ is bonded to twelve F1- atoms to form distorted BaF12 cuboctahedra that share corners with two equivalent BaF12 cuboctahedra, corners with two equivalent CuF6 octahedra, corners with four equivalent FeF6 octahedra, edges with four equivalent BaF12 cuboctahedra, edges with two equivalent FeF6 octahedra, edges with two equivalent CuF6 octahedra, and faces with two equivalent CuF6 octahedra. The corner-sharing octahedra tilt angles range from 41–51°. There are a spread of Ba–F bond distances ranging from 2.74–3.18 Å. Fe3+ is bonded to six F1- atoms to form FeF6 octahedra that share corners with three BaF12 cuboctahedra, a cornercorner with one FeF6 octahedra, corners with two equivalent CuF6 octahedra, edges with two BaF12 cuboctahedra, an edgeedge with one CuF6 octahedra, and a faceface with one BaF12 cuboctahedra. The corner-sharing octahedra tilt angles range from 49–56°. There are a spread of Fe–F bond distances ranging from 1.90–2.01 Å. Cu2+ is bonded to six F1- atoms to form CuF6 octahedra that share corners with three BaF12 cuboctahedra, a cornercorner with one CuF6 octahedra, corners with two equivalent FeF6 octahedra, edges with two BaF12 cuboctahedra, an edgeedge with one FeF6 octahedra, and a faceface with one BaF12 cuboctahedra. The corner-sharing octahedra tilt angles range from 50–56°. There are a spread of Cu–F bond distances ranging from 1.87–2.25 Å. There are eight inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted single-bond geometry to two Ba2+ and one Cu2+ atom. In the second F1- site, F1- is bonded in a distorted single-bond geometry to two Ba2+ and one Fe3+ atom. In the third F1- site, F1- is bonded in a 2-coordinate geometry to two Ba2+, one Fe3+, and one Cu2+ atom. In the fourth F1- site, F1- is bonded in a distorted water-like geometry to two Ba2+, one Fe3+, and one Cu2+ atom. In the fifth F1- site, F1- is bonded in a distorted bent 120 degrees geometry to one Ba2+, one Fe3+, and one Cu2+ atom. In the sixth F1- site, F1- is bonded in a distorted bent 120 degrees geometry to one Ba2+, one Fe3+, and one Cu2+ atom. In the seventh F1- site, F1- is bonded in a distorted bent 120 degrees geometry to two equivalent Ba2+ and two equivalent Cu2+ atoms. In the eighth F1- site, F1- is bonded in a distorted bent 120 degrees geometry to two equivalent Ba2+ and two equivalent Fe3+ atoms.