Materials Data on BaLaCo2O5 by Materials Project
LaBaCo2O5 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 CoO5 square pyramids. There are a spread of Ba–O bond distances ranging from 2.81–3.13 Å. La3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.51 Å) and four longer (2.53 Å) La–O bond lengths. Co+2.50+ is bonded to five O2- atoms to form CoO5 square pyramids that share corners with five equivalent CoO5 square pyramids and faces with four equivalent BaO12 cuboctahedra. There are a spread of Co–O bond distances ranging from 1.98–2.05 Å. 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 La3+, and two equivalent Co+2.50+ atoms. In the second O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Ba2+, two equivalent La3+, and two equivalent Co+2.50+ atoms. In the third O2- site, O2- is bonded to four equivalent Ba2+ and two equivalent Co+2.50+ atoms to form a mixture of distorted corner and edge-sharing OBa4Co2 octahedra. The corner-sharing octahedral tilt angles are 0°.