Materials Data on BaTi(SiO3)3 by Materials Project
BaTiSi3O9 crystallizes in the trigonal P31c space group. The structure is three-dimensional. there are three inequivalent Ba2+ sites. In the first 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 2.79–3.30 Å. In the second Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to six O2- atoms. All Ba–O bond lengths are 2.80 Å. In the third Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.79 Å) and three longer (2.80 Å) Ba–O bond lengths. Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six SiO4 tetrahedra. There are a spread of Ti–O bond distances ranging from 1.95–1.99 Å. There are three inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent TiO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 38–48°. There is two shorter (1.62 Å) and two longer (1.66 Å) Si–O bond length. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent TiO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 41–45°. There are a spread of Si–O bond distances ranging from 1.62–1.66 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent TiO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 41–45°. There are a spread of Si–O bond distances ranging from 1.63–1.66 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one Ba2+, one Ti4+, and one Si4+ atom. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Si4+ atoms. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Ba2+, one Ti4+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Si4+ atoms. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Ba2+, one Ti4+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one Ba2+, one Ti4+, and one Si4+ atom. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to one Ba2+, one Ti4+, and one Si4+ atom. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to one Ba2+, one Ti4+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Ba2+ and two Si4+ atoms.