Materials Data on Ba2Ti3O8 by Materials Project

Abstract

Ba2Ti3O8 crystallizes in the tetragonal P4/mmm space group. The structure is two-dimensional and consists of one Ba2Ti3O8 sheet oriented in the (0, 0, 1) direction. Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with eight equivalent BaO12 cuboctahedra, faces with five equivalent BaO12 cuboctahedra, faces with four equivalent TiO6 octahedra, and faces with four equivalent TiO5 square pyramids. There are eight shorter (2.79 Å) and four longer (2.92 Å) Ba–O bond lengths. There are two inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to five O2- atoms to form TiO5 square pyramids that share a cornercorner with one TiO6 octahedra, corners with four equivalent TiO5 square pyramids, and faces with four equivalent BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There is one shorter (1.91 Å) and four longer (1.98 Å) Ti–O bond length. In the second Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with four equivalent TiO6 octahedra, corners with two equivalent TiO5 square pyramids, and faces with eight equivalent BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (1.97 Å) and two longer (2.07 Å) Ti–O bond lengths. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to two equivalent Ba2+ and two equivalent Ti4+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ba2+ and two equivalent Ti4+ atoms. In the third O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ba2+ and two Ti4+ atoms.