Materials Data on Ba3Ta2NiO9 by Materials Project

Abstract

Ba3NiTa2O9 is (Cubic) Perovskite-derived structured and crystallizes in the trigonal P-3m1 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 twelve BaO12 cuboctahedra, faces with six BaO12 cuboctahedra, faces with three equivalent NiO6 octahedra, and faces with five equivalent TaO6 octahedra. There are nine shorter (2.91 Å) and three longer (2.95 Å) Ba–O bond lengths. In the second Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with twelve BaO12 cuboctahedra, faces with six equivalent BaO12 cuboctahedra, faces with two equivalent NiO6 octahedra, and faces with six equivalent TaO6 octahedra. There are six shorter (2.90 Å) and six longer (2.91 Å) Ba–O bond lengths. Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with three equivalent TaO6 octahedra, corners with three equivalent NiO6 octahedra, and faces with eight BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are three shorter (1.95 Å) and three longer (2.10 Å) Ta–O bond lengths. Ni2+ is bonded to six equivalent O2- atoms to form NiO6 octahedra that share corners with six equivalent TaO6 octahedra and faces with eight BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 3°. All Ni–O bond lengths are 2.14 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to four Ba2+, one Ta5+, and one Ni2+ atom. In the second O2- site, O2- is bonded in a distorted linear geometry to four Ba2+ and two equivalent Ta5+ atoms.