Materials Data on Ba4CaTi5O15 by Materials Project
Ba4CaTi5O15 is (Cubic) Perovskite-derived structured and crystallizes in the tetragonal P4/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 CaO12 cuboctahedra, corners with eight BaO12 cuboctahedra, a faceface with one CaO12 cuboctahedra, faces with five BaO12 cuboctahedra, and faces with eight TiO6 octahedra. There are a spread of Ba–O bond distances ranging from 2.83–2.91 Å. 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 BaO12 cuboctahedra, and faces with eight TiO6 octahedra. There are eight shorter (2.83 Å) and four longer (2.84 Å) Ba–O bond lengths. Ca2+ is bonded to twelve O2- atoms to form CaO12 cuboctahedra that share corners with four equivalent CaO12 cuboctahedra, corners with eight equivalent BaO12 cuboctahedra, faces with two equivalent BaO12 cuboctahedra, faces with four equivalent CaO12 cuboctahedra, and faces with eight equivalent TiO6 octahedra. There are eight shorter (2.74 Å) and four longer (2.83 Å) Ca–O bond lengths. There are three inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six TiO6 octahedra, faces with four equivalent BaO12 cuboctahedra, and faces with four equivalent CaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are a spread of Ti–O bond distances ranging from 1.92–2.05 Å. In the second Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six TiO6 octahedra and faces with eight BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are four shorter (2.00 Å) and two longer (2.02 Å) Ti–O bond lengths. In the third Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six TiO6 octahedra and faces with eight equivalent BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.00 Å) and two longer (2.01 Å) Ti–O bond lengths. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to four equivalent Ca2+ and two equivalent Ti4+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ba2+ and two Ti4+ atoms. In the third O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ba2+ and two Ti4+ atoms. In the fourth O2- site, O2- is bonded in a distorted linear geometry to two equivalent Ba2+, two equivalent Ca2+, and two equivalent Ti4+ atoms. In the fifth O2- site, O2- is bonded in a distorted linear geometry to four Ba2+ and two equivalent Ti4+ atoms. In the sixth O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ba2+ and two equivalent Ti4+ atoms.