Materials Data on Ba2TaCrO6 by Materials Project
Ba2TaCrO6 is (Cubic) Perovskite-derived structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are three 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 equivalent BaO12 cuboctahedra, faces with two equivalent CrO6 octahedra, and faces with six equivalent TaO6 octahedra. There are six shorter (2.87 Å) and six longer (2.91 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 TaO6 octahedra, and faces with six equivalent CrO6 octahedra. There are six shorter (2.91 Å) and six longer (2.98 Å) Ba–O bond lengths. In the third Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form distorted BaO12 cuboctahedra that share corners with nine equivalent BaO12 cuboctahedra, corners with three equivalent CrO6 octahedra, faces with seven BaO12 cuboctahedra, faces with three equivalent CrO6 octahedra, and faces with four equivalent TaO6 octahedra. The corner-sharing octahedral tilt angles are 7°. There are a spread of Ba–O bond distances ranging from 2.77–3.20 Å. Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with three equivalent TaO6 octahedra, corners with three equivalent CrO6 octahedra, and faces with eight BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are three shorter (1.97 Å) and three longer (2.07 Å) Ta–O bond lengths. Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with three equivalent BaO12 cuboctahedra, corners with three equivalent TaO6 octahedra, faces with seven BaO12 cuboctahedra, and a faceface with one CrO6 octahedra. The corner-sharing octahedral tilt angles are 1°. There are three shorter (2.01 Å) and three longer (2.08 Å) Cr–O bond lengths. 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 Ta5+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to four Ba2+, one Ta5+, and one Cr3+ atom. In the third O2- site, O2- is bonded in a 6-coordinate geometry to four Ba2+ and two equivalent Cr3+ atoms.