DOI: 10.17188/1710384
title: Materials Data on Ba8ZrNb19O36 by Materials Project

description: Ba8ZrNb19O36 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are four inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with eight BaO12 cuboctahedra, faces with five BaO12 cuboctahedra, faces with four equivalent NbO6 octahedra, and faces with four equivalent NbO5 square pyramids. There are a spread of Ba–O bond distances ranging from 2.90–2.99 Å. In the second Ba2+ site, 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 NbO6 octahedra, and faces with four equivalent NbO5 square pyramids. There are a spread of Ba–O bond distances ranging from 2.91–2.99 Å. In the third Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with eight BaO12 cuboctahedra, faces with five BaO12 cuboctahedra, faces with four equivalent NbO6 octahedra, and faces with four equivalent NbO5 square pyramids. There are a spread of Ba–O bond distances ranging from 2.91–2.99 Å. In the fourth Ba2+ site, 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 ZrO6 octahedra, and faces with four equivalent NbO5 square pyramids. There are a spread of Ba–O bond distances ranging from 2.93–2.99 Å. Zr2+ is bonded to six O2- atoms to form ZrO6 octahedra that share corners with four equivalent ZrO6 octahedra, corners with two equivalent NbO5 square pyramids, and faces with eight equivalent BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.11 Å) and four longer (2.12 Å) Zr–O bond lengths. There are eight inequivalent Nb+2.84+ sites. In the first Nb+2.84+ site, Nb+2.84+ is bonded in a square co-planar geometry to four O2- atoms. There are three shorter (2.12 Å) and one longer (2.14 Å) Nb–O bond lengths. In the second Nb+2.84+ site, Nb+2.84+ is bonded in a square co-planar geometry to four O2- atoms. There are a spread of Nb–O bond distances ranging from 2.12–2.14 Å. In the third Nb+2.84+ site, Nb+2.84+ is bonded to five O2- atoms to form NbO5 square pyramids that share a cornercorner with one NbO6 octahedra, corners with four equivalent NbO5 square pyramids, and faces with four equivalent BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.12 Å) and one longer (2.19 Å) Nb–O bond lengths. In the fourth Nb+2.84+ site, Nb+2.84+ is bonded to five O2- atoms to form NbO5 square pyramids that share a cornercorner with one NbO6 octahedra, corners with four equivalent NbO5 square pyramids, and faces with four equivalent BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.12 Å) and one longer (2.19 Å) Nb–O bond lengths. In the fifth Nb+2.84+ site, Nb+2.84+ is bonded to five O2- atoms to form NbO5 square pyramids that share a cornercorner with one NbO6 octahedra, corners with four equivalent NbO5 square pyramids, and faces with four equivalent BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.12 Å) and one longer (2.19 Å) Nb–O bond lengths. In the sixth Nb+2.84+ site, Nb+2.84+ is bonded to five O2- atoms to form NbO5 square pyramids that share a cornercorner with one ZrO6 octahedra, corners with four equivalent NbO5 square pyramids, and faces with four equivalent BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are one shorter (2.10 Å) and four longer (2.12 Å) Nb–O bond lengths. In the seventh Nb+2.84+ site, Nb+2.84+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with four equivalent NbO6 octahedra, corners with two NbO5 square pyramids, and faces with eight BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.01 Å) and four longer (2.12 Å) Nb–O bond lengths. In the eighth Nb+2.84+ site, Nb+2.84+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with four equivalent NbO6 octahedra, corners with two equivalent NbO5 square pyramids, and faces with eight equivalent BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.01 Å) and four longer (2.12 Å) Nb–O bond lengths. There are thirteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ba2+ and two Nb+2.84+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ba2+ and two Nb+2.84+ atoms. In the third O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ba2+ and two Nb+2.84+ atoms. In the fourth O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ba2+, one Zr2+, and one Nb+2.84+ atom. In the fifth O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ba2+ and two equivalent Zr2+ atoms. In the sixth O2- site, O2- is bonded in a distorted linear geometry to four Ba2+ and two equivalent Nb+2.84+ atoms. In the seventh O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ba2+ and two equivalent Nb+2.84+ atoms. In the eighth O2- site, O2- is bonded in a distorted T-shaped geometry to two equivalent Ba2+ and three Nb+2.84+ atoms. In the ninth O2- site, O2- is bonded in a distorted T-shaped geometry to two equivalent Ba2+ and three Nb+2.84+ atoms. In the tenth O2- site, O2- is bonded in a distorted T-shaped geometry to two equivalent Ba2+ and three Nb+2.84+ atoms. In the eleventh O2- site, O2- is bonded in a distorted T-shaped geometry to two equivalent Ba2+ and three Nb+2.84+ atoms. In the twelfth O2- site, O2- is bonded in a rectangular see-saw-like geometry to four equivalent Nb+2.84+ atoms. In the thirteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to four equivalent Nb+2.84+ atoms.