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Materials Data on BaLa2Fe2O5F4 by Materials Project

BaLa2Fe2O5F4 crystallizes in the orthorhombic Imm2 space group. The structure is three-dimensional. Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with four equivalent BaO12 cuboctahedra, corners with eight equivalent LaO4F8 cuboctahedra, faces with two equivalent LaO4F8 cuboctahedra, faces with four equivalent BaO12 cuboctahedra, and faces with eight equivalent FeO5F octahedra. There are a spread of Ba–O bond distances ranging from 2.84–3.04 Å. La3+ is bonded to four O2- and eight F1- atoms to form distorted LaO4F8 cuboctahedra that share corners with four equivalent BaO12 cuboctahedra, corners with four equivalent LaO4F8 cuboctahedra, edges with four equivalent LaO4F8 cuboctahedra, a faceface with one BaO12 cuboctahedra, faces with four equivalent LaO4F8 cuboctahedra, and faces with four equivalent FeO5F octahedra. There are a spread of La–O bond distances ranging from 2.59–2.67 Å. There are a spread of La–F bond distances ranging from 2.52–2.95 Å. Fe3+ is bonded to five O2- and one F1- atom to form FeO5F octahedra that share corners with five equivalent FeO5F octahedra, faces with four equivalent BaO12 cuboctahedra, and faces with four equivalent LaO4F8 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–17°. There are a spread of Fe–O bond distances ranging from 1.97–2.05 Å. The Fe–F bond length is 2.04 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+, two equivalent La3+, and two equivalent Fe3+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+, two equivalent La3+, and two equivalent Fe3+ atoms. In the third O2- site, O2- is bonded to four equivalent Ba2+ and two equivalent Fe3+ atoms to form a mixture of distorted corner and edge-sharing OBa4Fe2 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded to four equivalent La3+ atoms to form a mixture of distorted corner and edge-sharing FLa4 tetrahedra. In the second F1- site, F1- is bonded in a distorted single-bond geometry to four equivalent La3+ and one Fe3+ atom.

36 MATERIALS SCIENCE↗