Materials Data on Ba4Hf3O10 by Materials Project

Abstract

Ba4Hf3O10 crystallizes in the orthorhombic Cmce 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 eight equivalent BaO12 cuboctahedra, faces with five equivalent BaO12 cuboctahedra, and faces with eight HfO6 octahedra. There are a spread of Ba–O bond distances ranging from 2.85–3.09 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 2.70–2.98 Å. There are two inequivalent Hf4+ sites. In the first Hf4+ site, Hf4+ is bonded to six O2- atoms to form HfO6 octahedra that share corners with six HfO6 octahedra and faces with eight equivalent BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–9°. There are two shorter (2.10 Å) and four longer (2.11 Å) Hf–O bond lengths. In the second Hf4+ site, Hf4+ is bonded to six O2- atoms to form HfO6 octahedra that share corners with five HfO6 octahedra and faces with four equivalent BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–5°. There are a spread of Hf–O bond distances ranging from 2.09–2.13 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to four equivalent Ba2+ and two equivalent Hf4+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to four Ba2+ and two equivalent Hf4+ atoms. In the third O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ba2+ and two Hf4+ atoms. In the fourth O2- site, O2- is bonded to five equivalent Ba2+ and one Hf4+ atom to form a mixture of distorted corner and edge-sharing OBa5Hf octahedra. The corner-sharing octahedral tilt angles are 5°.