Materials Data on BaTbFe2O5 by Materials Project
TbBaFe2O5 crystallizes in the orthorhombic Pmmm 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, faces with four equivalent BaO12 cuboctahedra, and faces with eight equivalent FeO5 square pyramids. There are a spread of Ba–O bond distances ranging from 2.81–3.12 Å. Tb3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.44 Å) and four longer (2.45 Å) Tb–O bond lengths. Fe+2.50+ is bonded to five O2- atoms to form FeO5 square pyramids that share corners with five equivalent FeO5 square pyramids and faces with four equivalent BaO12 cuboctahedra. There are four shorter (2.02 Å) and one longer (2.04 Å) Fe–O bond lengths. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, two equivalent Tb3+, and two equivalent Fe+2.50+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, two equivalent Tb3+, and two equivalent Fe+2.50+ atoms. In the third O2- site, O2- is bonded to four equivalent Ba2+ and two equivalent Fe+2.50+ atoms to form a mixture of distorted edge and corner-sharing OBa4Fe2 octahedra. The corner-sharing octahedral tilt angles are 0°.