BaCoO3 crystallizes in the triclinic P1 space group. There are four inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to one O(10), one O(11), one O(12), one O(3), one O(4), one O(9), two equivalent O(1), two equivalent O(5), and two equivalent O(7) atoms to form BaO12 cuboctahedra that share corners with six equivalent Ba(1)O12 cuboctahedra, corners with three equivalent Co(2)O6 octahedra, corners with three equivalent Co(3)O6 octahedra, faces with two equivalent Ba(2)O12 cuboctahedra, faces with three equivalent Ba(3)O12 cuboctahedra, faces with three equivalent Ba(4)O12 cuboctahedra, faces with three equivalent Co(1)O6 octahedra, and faces with three equivalent Co(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-15°. In the second Ba site, Ba(2) is bonded to one O(10), one O(11), one O(12), one O(3), one O(4), one O(9), two equivalent O(2), two equivalent O(6), and two equivalent O(8) atoms to form BaO12 cuboctahedra that share corners with six equivalent Ba(2)O12 cuboctahedra, corners with three equivalent Co(1)O6 octahedra, corners with three equivalent Co(4)O6 octahedra, faces with two equivalent Ba(1)O12 cuboctahedra, faces with three equivalent Ba(3)O12 cuboctahedra, faces with three equivalent Ba(4)O12 cuboctahedra, faces with three equivalent Co(2)O6 octahedra, and faces with three equivalent Co(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-15°. In the third Ba site, Ba(3) is bonded to one O(1), one O(2), one O(5), one O(6), one O(7), one O(8), two equivalent O(11), two equivalent O(3), and two equivalent O(9) atoms to form BaO12 cuboctahedra that share corners with six equivalent Ba(3)O12 cuboctahedra, corners with three equivalent Co(1)O6 octahedra, corners with three equivalent Co(2)O6 octahedra, faces with two equivalent Ba(4)O12 cuboctahedra, faces with three equivalent Ba(1)O12 cuboctahedra, faces with three equivalent Ba(2)O12 cuboctahedra, faces with three equivalent Co(3)O6 octahedra, and faces with three equivalent Co(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-14°. In the fourth Ba site, Ba(4) is bonded to one O(1), one O(2), one O(5), one O(6), one O(7), one O(8), two equivalent O(10), two equivalent O(12), and two equivalent O(4) atoms to form BaO12 cuboctahedra that share corners with six equivalent Ba(4)O12 cuboctahedra, corners with three equivalent Co(3)O6 octahedra, corners with three equivalent Co(4)O6 octahedra, faces with two equivalent Ba(3)O12 cuboctahedra, faces with three equivalent Ba(1)O12 cuboctahedra, faces with three equivalent Ba(2)O12 cuboctahedra, faces with three equivalent Co(1)O6 octahedra, and faces with three equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-14°. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(10), one O(12), one O(4), one O(5), and one O(7) atom to form CoO6 octahedra that share corners with three equivalent Ba(2)O12 cuboctahedra, corners with three equivalent Ba(3)O12 cuboctahedra, faces with three equivalent Ba(1)O12 cuboctahedra, faces with three equivalent Ba(4)O12 cuboctahedra,  a faceface with one Co(2)O6 octahedra, and  a faceface with one Co(4)O6 octahedra. In the second Co site, Co(2) is bonded to one O(10), one O(12), one O(2), one O(4), one O(6), and one O(8) atom to form CoO6 octahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, corners with three equivalent Ba(3)O12 cuboctahedra, faces with three equivalent Ba(2)O12 cuboctahedra, faces with three equivalent Ba(4)O12 cuboctahedra,  a faceface with one Co(1)O6 octahedra, and  a faceface with one Co(3)O6 octahedra. In the third Co site, Co(3) is bonded to one O(11), one O(2), one O(3), one O(6), one O(8), and one O(9) atom to form CoO6 octahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, corners with three equivalent Ba(4)O12 cuboctahedra, faces with three equivalent Ba(2)O12 cuboctahedra, faces with three equivalent Ba(3)O12 cuboctahedra,  a faceface with one Co(2)O6 octahedra, and  a faceface with one Co(4)O6 octahedra. In the fourth Co site, Co(4) is bonded to one O(1), one O(11), one O(3), one O(5), one O(7), and one O(9) atom to form CoO6 octahedra that share corners with three equivalent Ba(2)O12 cuboctahedra, corners with three equivalent Ba(4)O12 cuboctahedra, faces with three equivalent Ba(1)O12 cuboctahedra, faces with three equivalent Ba(3)O12 cuboctahedra,  a faceface with one Co(1)O6 octahedra, and  a faceface with one Co(3)O6 octahedra. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Ba(3), one Ba(4), two equivalent Ba(1), one Co(1), and one Co(4) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Ba(3), one Ba(4), two equivalent Ba(2), one Co(2), and one Co(3) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(2), two equivalent Ba(3), one Co(3), and one Co(4) atom. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(2), two equivalent Ba(4), one Co(1), and one Co(2) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one Ba(3), one Ba(4), two equivalent Ba(1), one Co(1), and one Co(4) atom. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Ba(3), one Ba(4), two equivalent Ba(2), one Co(2), and one Co(3) atom. In the seventh O site, O(7) is bonded in a 2-coordinate geometry to one Ba(3), one Ba(4), two equivalent Ba(1), one Co(1), and one Co(4) atom. In the eighth O site, O(8) is bonded in a 2-coordinate geometry to one Ba(3), one Ba(4), two equivalent Ba(2), one Co(2), and one Co(3) atom. In the ninth O site, O(9) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(2), two equivalent Ba(3), one Co(3), and one Co(4) atom. In the tenth O site, O(10) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(2), two equivalent Ba(4), one Co(1), and one Co(2) atom. In the eleventh O site, O(11) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(2), two equivalent Ba(3), one Co(3), and one Co(4) atom. In the twelfth O site, O(12) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(2), two equivalent Ba(4), one Co(1), and one Co(2) atom.
BaCoO3 crystallizes in the triclinic P1 space group. There are four inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to one O(10), one O(11), one O(12), one O(3), one O(4), one O(9), two equivalent O(1), two equivalent O(5), and two equivalent O(7) atoms to form BaO12 cuboctahedra that share corners with six equivalent Ba(1)O12 cuboctahedra, corners with three equivalent Co(2)O6 octahedra, corners with three equivalent Co(3)O6 octahedra, faces with two equivalent Ba(2)O12 cuboctahedra, faces with three equivalent Ba(3)O12 cuboctahedra, faces with three equivalent Ba(4)O12 cuboctahedra, faces with three equivalent Co(1)O6 octahedra, and faces with three equivalent Co(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-15°. The Ba(1)-O(10) bond length is 3.03 Å. The Ba(1)-O(11) bond length is 3.02 Å. The Ba(1)-O(12) bond length is 3.09 Å. The Ba(1)-O(3) bond length is 3.07 Å. The Ba(1)-O(4) bond length is 3.05 Å. The Ba(1)-O(9) bond length is 3.06 Å. Both Ba(1)-O(1) bond lengths are 2.87 Å. Both Ba(1)-O(5) bond lengths are 2.87 Å. Both Ba(1)-O(7) bond lengths are 2.87 Å. In the second Ba site, Ba(2) is bonded to one O(10), one O(11), one O(12), one O(3), one O(4), one O(9), two equivalent O(2), two equivalent O(6), and two equivalent O(8) atoms to form BaO12 cuboctahedra that share corners with six equivalent Ba(2)O12 cuboctahedra, corners with three equivalent Co(1)O6 octahedra, corners with three equivalent Co(4)O6 octahedra, faces with two equivalent Ba(1)O12 cuboctahedra, faces with three equivalent Ba(3)O12 cuboctahedra, faces with three equivalent Ba(4)O12 cuboctahedra, faces with three equivalent Co(2)O6 octahedra, and faces with three equivalent Co(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-15°. The Ba(2)-O(10) bond length is 3.08 Å. The Ba(2)-O(11) bond length is 3.09 Å. The Ba(2)-O(12) bond length is 3.02 Å. The Ba(2)-O(3) bond length is 3.04 Å. The Ba(2)-O(4) bond length is 3.06 Å. The Ba(2)-O(9) bond length is 3.03 Å. Both Ba(2)-O(2) bond lengths are 2.87 Å. Both Ba(2)-O(6) bond lengths are 2.87 Å. Both Ba(2)-O(8) bond lengths are 2.87 Å. In the third Ba site, Ba(3) is bonded to one O(1), one O(2), one O(5), one O(6), one O(7), one O(8), two equivalent O(11), two equivalent O(3), and two equivalent O(9) atoms to form BaO12 cuboctahedra that share corners with six equivalent Ba(3)O12 cuboctahedra, corners with three equivalent Co(1)O6 octahedra, corners with three equivalent Co(2)O6 octahedra, faces with two equivalent Ba(4)O12 cuboctahedra, faces with three equivalent Ba(1)O12 cuboctahedra, faces with three equivalent Ba(2)O12 cuboctahedra, faces with three equivalent Co(3)O6 octahedra, and faces with three equivalent Co(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-14°. The Ba(3)-O(1) bond length is 3.03 Å. The Ba(3)-O(2) bond length is 3.09 Å. The Ba(3)-O(5) bond length is 3.06 Å. The Ba(3)-O(6) bond length is 3.04 Å. The Ba(3)-O(7) bond length is 3.08 Å. The Ba(3)-O(8) bond length is 3.02 Å. There is one shorter (2.86 Å) and one longer (2.87 Å) Ba(3)-O(11) bond length. Both Ba(3)-O(3) bond lengths are 2.87 Å. Both Ba(3)-O(9) bond lengths are 2.87 Å. In the fourth Ba site, Ba(4) is bonded to one O(1), one O(2), one O(5), one O(6), one O(7), one O(8), two equivalent O(10), two equivalent O(12), and two equivalent O(4) atoms to form BaO12 cuboctahedra that share corners with six equivalent Ba(4)O12 cuboctahedra, corners with three equivalent Co(3)O6 octahedra, corners with three equivalent Co(4)O6 octahedra, faces with two equivalent Ba(3)O12 cuboctahedra, faces with three equivalent Ba(1)O12 cuboctahedra, faces with three equivalent Ba(2)O12 cuboctahedra, faces with three equivalent Co(1)O6 octahedra, and faces with three equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-14°. The Ba(4)-O(1) bond length is 3.09 Å. The Ba(4)-O(2) bond length is 3.02 Å. The Ba(4)-O(5) bond length is 3.05 Å. The Ba(4)-O(6) bond length is 3.07 Å. The Ba(4)-O(7) bond length is 3.03 Å. The Ba(4)-O(8) bond length is 3.06 Å. Both Ba(4)-O(10) bond lengths are 2.87 Å. Both Ba(4)-O(12) bond lengths are 2.87 Å. Both Ba(4)-O(4) bond lengths are 2.87 Å. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(10), one O(12), one O(4), one O(5), and one O(7) atom to form CoO6 octahedra that share corners with three equivalent Ba(2)O12 cuboctahedra, corners with three equivalent Ba(3)O12 cuboctahedra, faces with three equivalent Ba(1)O12 cuboctahedra, faces with three equivalent Ba(4)O12 cuboctahedra,  a faceface with one Co(2)O6 octahedra, and  a faceface with one Co(4)O6 octahedra. The Co(1)-O(1) bond length is 1.93 Å. The Co(1)-O(10) bond length is 1.87 Å. The Co(1)-O(12) bond length is 1.93 Å. The Co(1)-O(4) bond length is 1.89 Å. The Co(1)-O(5) bond length is 1.88 Å. The Co(1)-O(7) bond length is 1.87 Å. In the second Co site, Co(2) is bonded to one O(10), one O(12), one O(2), one O(4), one O(6), and one O(8) atom to form CoO6 octahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, corners with three equivalent Ba(3)O12 cuboctahedra, faces with three equivalent Ba(2)O12 cuboctahedra, faces with three equivalent Ba(4)O12 cuboctahedra,  a faceface with one Co(1)O6 octahedra, and  a faceface with one Co(3)O6 octahedra. The Co(2)-O(10) bond length is 1.92 Å. The Co(2)-O(12) bond length is 1.86 Å. The Co(2)-O(2) bond length is 1.85 Å. The Co(2)-O(4) bond length is 1.90 Å. The Co(2)-O(6) bond length is 1.91 Å. The Co(2)-O(8) bond length is 1.92 Å. In the third Co site, Co(3) is bonded to one O(11), one O(2), one O(3), one O(6), one O(8), and one O(9) atom to form CoO6 octahedra that share corners with three equivalent Ba(1)O12 cuboctahedra, corners with three equivalent Ba(4)O12 cuboctahedra, faces with three equivalent Ba(2)O12 cuboctahedra, faces with three equivalent Ba(3)O12 cuboctahedra,  a faceface with one Co(2)O6 octahedra, and  a faceface with one Co(4)O6 octahedra. The Co(3)-O(11) bond length is 1.93 Å. The Co(3)-O(2) bond length is 1.93 Å. The Co(3)-O(3) bond length is 1.87 Å. The Co(3)-O(6) bond length is 1.87 Å. The Co(3)-O(8) bond length is 1.88 Å. The Co(3)-O(9) bond length is 1.89 Å. In the fourth Co site, Co(4) is bonded to one O(1), one O(11), one O(3), one O(5), one O(7), and one O(9) atom to form CoO6 octahedra that share corners with three equivalent Ba(2)O12 cuboctahedra, corners with three equivalent Ba(4)O12 cuboctahedra, faces with three equivalent Ba(1)O12 cuboctahedra, faces with three equivalent Ba(3)O12 cuboctahedra,  a faceface with one Co(1)O6 octahedra, and  a faceface with one Co(3)O6 octahedra. The Co(4)-O(1) bond length is 1.86 Å. The Co(4)-O(11) bond length is 1.85 Å. The Co(4)-O(3) bond length is 1.92 Å. The Co(4)-O(5) bond length is 1.90 Å. The Co(4)-O(7) bond length is 1.92 Å. The Co(4)-O(9) bond length is 1.91 Å. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Ba(3), one Ba(4), two equivalent Ba(1), one Co(1), and one Co(4) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Ba(3), one Ba(4), two equivalent Ba(2), one Co(2), and one Co(3) atom. In the third O site, O(3) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(2), two equivalent Ba(3), one Co(3), and one Co(4) atom. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(2), two equivalent Ba(4), one Co(1), and one Co(2) atom. In the fifth O site, O(5) is bonded in a 2-coordinate geometry to one Ba(3), one Ba(4), two equivalent Ba(1), one Co(1), and one Co(4) atom. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Ba(3), one Ba(4), two equivalent Ba(2), one Co(2), and one Co(3) atom. In the seventh O site, O(7) is bonded in a 2-coordinate geometry to one Ba(3), one Ba(4), two equivalent Ba(1), one Co(1), and one Co(4) atom. In the eighth O site, O(8) is bonded in a 2-coordinate geometry to one Ba(3), one Ba(4), two equivalent Ba(2), one Co(2), and one Co(3) atom. In the ninth O site, O(9) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(2), two equivalent Ba(3), one Co(3), and one Co(4) atom. In the tenth O site, O(10) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(2), two equivalent Ba(4), one Co(1), and one Co(2) atom. In the eleventh O site, O(11) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(2), two equivalent Ba(3), one Co(3), and one Co(4) atom. In the twelfth O site, O(12) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(2), two equivalent Ba(4), one Co(1), and one Co(2) atom.