Ba3CaRu2O9 is (Cubic) Perovskite-derived structured and crystallizes in the hexagonal P-62c 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 Ca(1)O6 octahedra, and faces with six equivalent Ru(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 Ru(1)O6 octahedra, faces with three equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ba(2)O12 cuboctahedra, faces with three equivalent Ca(1)O6 octahedra, and faces with four equivalent Ru(1)O6 octahedra. The corner-sharing octahedral tilt angles are 9°. Ca(1) is bonded to six equivalent O(2) atoms to form CaO6 octahedra that share corners with six equivalent Ru(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 6°. Ru(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form RuO6 octahedra that share corners with three equivalent Ba(2)O12 cuboctahedra, corners with three equivalent Ca(1)O6 octahedra, faces with three equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ba(2)O12 cuboctahedra, and  a faceface with one Ru(1)O6 octahedra. The corner-sharing octahedral tilt angles are 6°. 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 Ru(1) atoms to form a mixture of distorted face and corner-sharing OBa4Ru2 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 Ca(1), and one Ru(1) atom.
Ba3CaRu2O9 is (Cubic) Perovskite-derived structured and crystallizes in the hexagonal P-62c 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 Ca(1)O6 octahedra, and faces with six equivalent Ru(1)O6 octahedra. There are three shorter (2.93 Å) and three longer (3.06 Å) Ba(1)-O(1) bond lengths. All Ba(1)-O(2) bond lengths are 3.00 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 Ru(1)O6 octahedra, faces with three equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ba(2)O12 cuboctahedra, faces with three equivalent Ca(1)O6 octahedra, and faces with four equivalent Ru(1)O6 octahedra. The corner-sharing octahedral tilt angles are 9°. All Ba(2)-O(1) bond lengths are 2.96 Å. There are a spread of Ba(2)-O(2) bond distances ranging from 2.92-3.23 Å. Ca(1) is bonded to six equivalent O(2) atoms to form CaO6 octahedra that share corners with six equivalent Ru(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 6°. All Ca(1)-O(2) bond lengths are 2.27 Å. Ru(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form RuO6 octahedra that share corners with three equivalent Ba(2)O12 cuboctahedra, corners with three equivalent Ca(1)O6 octahedra, faces with three equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ba(2)O12 cuboctahedra, and  a faceface with one Ru(1)O6 octahedra. The corner-sharing octahedral tilt angles are 6°. All Ru(1)-O(1) bond lengths are 2.08 Å. All Ru(1)-O(2) bond lengths are 1.91 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 Ru(1) atoms to form a mixture of distorted face and corner-sharing OBa4Ru2 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 Ca(1), and one Ru(1) atom.