Ba6ZrO8 crystallizes in the cubic Fm-3m space group. Ba(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form BaO6 octahedra that share corners with six equivalent Ba(1)O6 octahedra, edges with two equivalent Zr(1)O6 octahedra, and edges with eight equivalent Ba(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-22°. Zr(1) is bonded to six equivalent O(1) atoms to form ZrO6 octahedra that share edges with twelve equivalent Ba(1)O6 octahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Ba(1) and one Zr(1) atom to form distorted OBa4Zr square pyramids that share corners with nine equivalent O(1)Ba4Zr square pyramids, edges with four equivalent O(2)Ba6 octahedra, and edges with four equivalent O(1)Ba4Zr square pyramids. In the second O site, O(2) is bonded to six equivalent Ba(1) atoms to form OBa6 octahedra that share corners with six equivalent O(2)Ba6 octahedra and edges with twelve equivalent O(1)Ba4Zr square pyramids. The corner-sharing octahedra are not tilted.
Ba6ZrO8 crystallizes in the cubic Fm-3m space group. Ba(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form BaO6 octahedra that share corners with six equivalent Ba(1)O6 octahedra, edges with two equivalent Zr(1)O6 octahedra, and edges with eight equivalent Ba(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-22°. Both Ba(1)-O(2) bond lengths are 2.73 Å. All Ba(1)-O(1) bond lengths are 2.78 Å. Zr(1) is bonded to six equivalent O(1) atoms to form ZrO6 octahedra that share edges with twelve equivalent Ba(1)O6 octahedra. All Zr(1)-O(1) bond lengths are 2.19 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Ba(1) and one Zr(1) atom to form distorted OBa4Zr square pyramids that share corners with nine equivalent O(1)Ba4Zr square pyramids, edges with four equivalent O(2)Ba6 octahedra, and edges with four equivalent O(1)Ba4Zr square pyramids. In the second O site, O(2) is bonded to six equivalent Ba(1) atoms to form OBa6 octahedra that share corners with six equivalent O(2)Ba6 octahedra and edges with twelve equivalent O(1)Ba4Zr square pyramids. The corner-sharing octahedra are not tilted.