Materials Data on Ba3Zr2O7 by Materials Project
Ba3Zr2O7 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, 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 ZrO6 octahedra. All Ba–O bond lengths are 3.01 Å. In the second Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ba–O bond distances ranging from 2.68–3.01 Å. Zr4+ is bonded to six O2- atoms to form ZrO6 octahedra that share corners with five equivalent ZrO6 octahedra and faces with four equivalent BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of Zr–O bond distances ranging from 2.12–2.15 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to four Ba2+ and two equivalent Zr4+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ba2+ and two equivalent Zr4+ atoms. In the third O2- site, O2- is bonded to five equivalent Ba2+ and one Zr4+ atom to form a mixture of distorted edge and corner-sharing OBa5Zr octahedra. The corner-sharing octahedral tilt angles are 6°.