Materials Data on Ba6Y2Ti4O17 by Materials Project

Abstract

Ba6Y2Ti4O17 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are four inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are three shorter (2.75 Å) and six longer (3.04 Å) Ba–O bond lengths. In the second Ba2+ site, Ba2+ is bonded in a 1-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.56–3.02 Å. In the third Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to six equivalent O2- atoms. All Ba–O bond lengths are 2.91 Å. In the fourth Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with six equivalent BaO12 cuboctahedra, faces with two equivalent YO6 octahedra, and faces with six equivalent TiO6 octahedra. There are six shorter (3.01 Å) and six longer (3.02 Å) Ba–O bond lengths. Y3+ is bonded to six O2- atoms to form YO6 octahedra that share corners with three equivalent TiO6 octahedra, corners with three equivalent TiO4 tetrahedra, and a faceface with one BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 3°. There are three shorter (2.23 Å) and three longer (2.29 Å) Y–O bond lengths. There are two inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with three equivalent YO6 octahedra, faces with three equivalent BaO12 cuboctahedra, and a faceface with one TiO6 octahedra. The corner-sharing octahedral tilt angles are 3°. There are three shorter (1.93 Å) and three longer (2.07 Å) Ti–O bond lengths. In the second Ti4+ site, Ti4+ is bonded to four O2- atoms to form TiO4 tetrahedra that share corners with three equivalent YO6 octahedra. The corner-sharing octahedral tilt angles are 19°. There is one shorter (1.78 Å) and three longer (1.85 Å) Ti–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to three Ba2+, one Y3+, and one Ti4+ atom. In the second O2- site, O2- is bonded in a distorted linear geometry to one Ba2+ and one Ti4+ atom. In the third O2- site, O2- is bonded in a 6-coordinate geometry to four Ba2+ and two equivalent Ti4+ atoms. In the fourth O2- site, O2- is bonded in a distorted linear geometry to four Ba2+, one Y3+, and one Ti4+ atom.