Materials Data on Sr3CaTi4O12 by Materials Project
Sr3CaTi4O12 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form distorted SrO12 cuboctahedra that share corners with six equivalent SrO12 cuboctahedra, faces with six equivalent SrO12 cuboctahedra, and faces with eight TiO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.59–2.98 Å. In the second Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form distorted SrO12 cuboctahedra that share corners with twelve equivalent SrO12 cuboctahedra, faces with three equivalent SrO12 cuboctahedra, and faces with eight TiO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.56–3.01 Å. Ca2+ is bonded in a 12-coordinate geometry to eleven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.45–3.01 Å. 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 six TiO6 octahedra and faces with five SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 10–20°. There are a spread of Ti–O bond distances ranging from 1.96–2.00 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 seven SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 7–13°. There are a spread of Ti–O bond distances ranging from 1.96–1.99 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to three Sr2+, one Ca2+, and two Ti4+ atoms. In the second O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Sr2+, one Ca2+, and two equivalent Ti4+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to four Sr2+ and two equivalent Ti4+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to four Sr2+ and two equivalent Ti4+ atoms. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Sr2+, two equivalent Ca2+, and two equivalent Ti4+ atoms. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to three Sr2+, one Ca2+, and two Ti4+ atoms. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to three Sr2+, one Ca2+, and two Ti4+ atoms.