DOE OSTI2020
Ba4Zr3TiO12 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 twelve BaO12 cuboctahedra, faces with six BaO12 cuboctahedra, faces with four equivalent ZrO6 octahedra, and faces with four equivalent TiO6 octahedra. There are a spread of Ba–O bond distances ranging from 2.87–3.04 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 ZrO6 octahedra. There are eight shorter (2.98 Å) and four longer (3.00 Å) Ba–O bond lengths. There are two inequivalent Zr4+ sites. In the first Zr4+ site, Zr4+ is bonded to six O2- atoms to form ZrO6 octahedra that share a cornercorner with one TiO6 octahedra, corners with five ZrO6 octahedra, and faces with eight BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of Zr–O bond distances ranging from 2.11–2.18 Å. In the second Zr4+ site, Zr4+ is bonded to six O2- atoms to form ZrO6 octahedra that share corners with six ZrO6 octahedra and faces with eight equivalent BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.11 Å) and two longer (2.13 Å) Zr–O bond lengths. Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two equivalent ZrO6 octahedra, corners with four equivalent TiO6 octahedra, and faces with eight equivalent BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (1.95 Å) and four longer (2.11 Å) Ti–O bond lengths. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to four equivalent Ba2+ and two equivalent Ti4+ atoms to form a mixture of distorted edge, face, and corner-sharing OBa4Ti2 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second O2- site, O2- is bonded in a distorted linear geometry to four Ba2+ and two equivalent Zr4+ atoms. In the third O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ba2+ and two equivalent Zr4+ atoms. In the fourth O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ba2+, one Zr4+, and one Ti4+ atom. In the fifth O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ba2+ and two Zr4+ atoms.