Ba3NiSb2O9 is (Cubic) Perovskite-derived structured and crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to six equivalent O(1) and six equivalent O(2) atoms to form BaO12 cuboctahedra that share corners with six equivalent Ba(1)O12 cuboctahedra, corners with six equivalent Ba(2)O12 cuboctahedra, faces with six equivalent Ba(2)O12 cuboctahedra, faces with two equivalent Ni(1)O6 octahedra, and faces with six equivalent Sb(1)O6 octahedra. In the second Ba site, Ba(2) is bonded to three equivalent O(1) and nine equivalent O(2) atoms to form BaO12 cuboctahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, corners with six equivalent Ba(2)O12 cuboctahedra, corners with three equivalent Sb(1)O6 octahedra, faces with three equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ba(2)O12 cuboctahedra, faces with three equivalent Ni(1)O6 octahedra, and faces with four equivalent Sb(1)O6 octahedra. The corner-sharing octahedral tilt angles are 8°. Ni(1) is bonded to six equivalent O(2) atoms to form NiO6 octahedra that share corners with six equivalent Sb(1)O6 octahedra, faces with two equivalent Ba(1)O12 cuboctahedra, and faces with six equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 5°. Sb(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form SbO6 octahedra that share corners with three equivalent Ba(2)O12 cuboctahedra, corners with three equivalent Ni(1)O6 octahedra, faces with three equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ba(2)O12 cuboctahedra, and  a faceface with one Sb(1)O6 octahedra. The corner-sharing octahedral tilt angles are 5°. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Sb(1) atoms to form a mixture of distorted corner and face-sharing OBa4Sb2 octahedra. The corner-sharing octahedral tilt angles range from 7-60°. In the second O site, O(2) is bonded in a distorted linear geometry to one Ba(1), three equivalent Ba(2), one Ni(1), and one Sb(1) atom.
Ba3NiSb2O9 is (Cubic) Perovskite-derived structured and crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to six equivalent O(1) and six equivalent O(2) atoms to form BaO12 cuboctahedra that share corners with six equivalent Ba(1)O12 cuboctahedra, corners with six equivalent Ba(2)O12 cuboctahedra, faces with six equivalent Ba(2)O12 cuboctahedra, faces with two equivalent Ni(1)O6 octahedra, and faces with six equivalent Sb(1)O6 octahedra. All Ba(1)-O(1) bond lengths are 2.97 Å. All Ba(1)-O(2) bond lengths are 2.99 Å. In the second Ba site, Ba(2) is bonded to three equivalent O(1) and nine equivalent O(2) atoms to form BaO12 cuboctahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, corners with six equivalent Ba(2)O12 cuboctahedra, corners with three equivalent Sb(1)O6 octahedra, faces with three equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ba(2)O12 cuboctahedra, faces with three equivalent Ni(1)O6 octahedra, and faces with four equivalent Sb(1)O6 octahedra. The corner-sharing octahedral tilt angles are 8°. All Ba(2)-O(1) bond lengths are 3.05 Å. There are six shorter (2.96 Å) and three longer (3.01 Å) Ba(2)-O(2) bond lengths. Ni(1) is bonded to six equivalent O(2) atoms to form NiO6 octahedra that share corners with six equivalent Sb(1)O6 octahedra, faces with two equivalent Ba(1)O12 cuboctahedra, and faces with six equivalent Ba(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 5°. All Ni(1)-O(2) bond lengths are 2.12 Å. Sb(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form SbO6 octahedra that share corners with three equivalent Ba(2)O12 cuboctahedra, corners with three equivalent Ni(1)O6 octahedra, faces with three equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ba(2)O12 cuboctahedra, and  a faceface with one Sb(1)O6 octahedra. The corner-sharing octahedral tilt angles are 5°. All Sb(1)-O(1) bond lengths are 2.10 Å. All Sb(1)-O(2) bond lengths are 1.96 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Sb(1) atoms to form a mixture of distorted corner and face-sharing OBa4Sb2 octahedra. The corner-sharing octahedral tilt angles range from 7-60°. In the second O site, O(2) is bonded in a distorted linear geometry to one Ba(1), three equivalent Ba(2), one Ni(1), and one Sb(1) atom.