Ba8Cu8O19 crystallizes in the triclinic P1 space group. There are eight inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to one O(13), one O(15), one O(17), one O(18), one O(19), one O(3), one O(4), one O(7), and two equivalent O(1) atoms. In the second Ba site, Ba(2) is bonded in a 10-coordinate geometry to one O(14), one O(16), one O(17), one O(18), one O(19), one O(3), one O(5), one O(6), and two equivalent O(2) atoms. In the third Ba site, Ba(3) is bonded in a 10-coordinate geometry to one O(1), one O(10), one O(18), one O(19), one O(2), one O(4), one O(5), one O(6), one O(7), and one O(9) atom. In the fourth Ba site, Ba(4) is bonded in a 9-coordinate geometry to one O(11), one O(12), one O(3), one O(4), one O(5), one O(6), one O(7), and two equivalent O(8) atoms. In the fifth Ba site, Ba(5) is bonded in a 10-coordinate geometry to one O(10), one O(12), one O(13), one O(15), one O(4), one O(7), one O(8), one O(9), and two equivalent O(11) atoms. In the sixth Ba site, Ba(6) is bonded in a 8-coordinate geometry to one O(10), one O(12), one O(14), one O(16), one O(5), one O(6), one O(8), and one O(9) atom. In the seventh Ba site, Ba(7) is bonded in a 9-coordinate geometry to one O(10), one O(11), one O(13), one O(14), one O(15), one O(16), one O(18), one O(19), and one O(9) atom. In the eighth Ba site, Ba(8) is bonded in a 10-coordinate geometry to one O(1), one O(12), one O(13), one O(14), one O(15), one O(16), one O(2), one O(3), and two equivalent O(17) atoms. There are eight inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(2), one O(3), one O(5), one O(6), and one O(8) atom to form a mixture of edge and corner-sharing CuO5 square pyramids. In the second Cu site, Cu(2) is bonded to one O(1), one O(3), one O(4), one O(7), and one O(8) atom to form a mixture of edge and corner-sharing CuO5 square pyramids. In the third Cu site, Cu(3) is bonded to one O(10), one O(11), one O(4), one O(7), and one O(9) atom to form corner-sharing CuO5 square pyramids. In the fourth Cu site, Cu(4) is bonded in a rectangular see-saw-like geometry to one O(10), one O(5), one O(6), and one O(9) atom. In the fifth Cu site, Cu(5) is bonded to one O(11), one O(12), one O(13), one O(15), and one O(17) atom to form CuO5 square pyramids that share  a cornercorner with one Cu(3)O5 square pyramid, corners with two equivalent Cu(8)O5 square pyramids, and  an edgeedge with one Cu(6)O4 tetrahedra. In the sixth Cu site, Cu(6) is bonded to one O(12), one O(14), one O(16), and one O(17) atom to form a mixture of distorted edge and corner-sharing CuO4 tetrahedra. In the seventh Cu site, Cu(7) is bonded to one O(14), one O(16), one O(18), one O(19), and one O(2) atom to form CuO5 square pyramids that share  a cornercorner with one Cu(1)O5 square pyramid, corners with two equivalent Cu(6)O4 tetrahedra, and  an edgeedge with one Cu(8)O5 square pyramid. In the eighth Cu site, Cu(8) is bonded to one O(1), one O(13), one O(15), one O(18), and one O(19) atom to form a mixture of edge and corner-sharing CuO5 square pyramids. There are nineteen inequivalent O sites. In the first O site, O(1) is bonded to one Ba(3), one Ba(8), two equivalent Ba(1), one Cu(2), and one Cu(8) atom to form a mixture of distorted edge, corner, and face-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 11-69°. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Ba(3), one Ba(8), two equivalent Ba(2), one Cu(1), and one Cu(7) atom. In the third O site, O(3) is bonded in a distorted L-shaped geometry to one Ba(1), one Ba(2), one Ba(4), one Ba(8), one Cu(1), and one Cu(2) atom. In the fourth O site, O(4) is bonded to one Ba(1), one Ba(3), one Ba(4), one Ba(5), one Cu(2), and one Cu(3) atom to form a mixture of distorted corner and face-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 1-72°. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to one Ba(2), one Ba(3), one Ba(4), one Ba(6), one Cu(1), and one Cu(4) atom. In the sixth O site, O(6) is bonded to one Ba(2), one Ba(3), one Ba(4), one Ba(6), one Cu(1), and one Cu(4) atom to form a mixture of distorted corner and face-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 29-72°. In the seventh O site, O(7) is bonded to one Ba(1), one Ba(3), one Ba(4), one Ba(5), one Cu(2), and one Cu(3) atom to form a mixture of distorted edge, corner, and face-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 13-69°. In the eighth O site, O(8) is bonded to one Ba(5), one Ba(6), two equivalent Ba(4), one Cu(1), and one Cu(2) atom to form a mixture of distorted corner and face-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 4-62°. In the ninth O site, O(9) is bonded to one Ba(3), one Ba(5), one Ba(6), one Ba(7), one Cu(3), and one Cu(4) atom to form a mixture of distorted edge, corner, and face-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 5-66°. In the tenth O site, O(10) is bonded in a distorted L-shaped geometry to one Ba(3), one Ba(5), one Ba(6), one Ba(7), one Cu(3), and one Cu(4) atom. In the eleventh O site, O(11) is bonded in a 6-coordinate geometry to one Ba(4), one Ba(7), two equivalent Ba(5), one Cu(3), and one Cu(5) atom. In the twelfth O site, O(12) is bonded in a 2-coordinate geometry to one Ba(4), one Ba(5), one Ba(6), one Ba(8), one Cu(5), and one Cu(6) atom. In the thirteenth O site, O(13) is bonded to one Ba(1), one Ba(5), one Ba(7), one Ba(8), one Cu(5), and one Cu(8) atom to form a mixture of distorted corner and face-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 1-65°. In the fourteenth O site, O(14) is bonded in a 2-coordinate geometry to one Ba(2), one Ba(6), one Ba(7), one Ba(8), one Cu(6), and one Cu(7) atom. In the fifteenth O site, O(15) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(5), one Ba(7), one Ba(8), one Cu(5), and one Cu(8) atom. In the sixteenth O site, O(16) is bonded in a 6-coordinate geometry to one Ba(2), one Ba(6), one Ba(7), one Ba(8), one Cu(6), and one Cu(7) atom. In the seventeenth O site, O(17) is bonded to one Ba(1), one Ba(2), two equivalent Ba(8), one Cu(5), and one Cu(6) atom to form a mixture of distorted edge, corner, and face-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 3-64°. In the eighteenth O site, O(18) is bonded in a distorted L-shaped geometry to one Ba(1), one Ba(2), one Ba(3), one Ba(7), one Cu(7), and one Cu(8) atom. In the nineteenth O site, O(19) is bonded to one Ba(1), one Ba(2), one Ba(3), one Ba(7), one Cu(7), and one Cu(8) atom to form a mixture of distorted edge, corner, and face-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 5-61°.
Ba8Cu8O19 crystallizes in the triclinic P1 space group. There are eight inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to one O(13), one O(15), one O(17), one O(18), one O(19), one O(3), one O(4), one O(7), and two equivalent O(1) atoms. The Ba(1)-O(13) bond length is 2.92 Å. The Ba(1)-O(15) bond length is 2.87 Å. The Ba(1)-O(17) bond length is 2.71 Å. The Ba(1)-O(18) bond length is 3.13 Å. The Ba(1)-O(19) bond length is 2.88 Å. The Ba(1)-O(3) bond length is 3.09 Å. The Ba(1)-O(4) bond length is 2.84 Å. The Ba(1)-O(7) bond length is 2.90 Å. There is one shorter (2.88 Å) and one longer (2.91 Å) Ba(1)-O(1) bond length. In the second Ba site, Ba(2) is bonded in a 10-coordinate geometry to one O(14), one O(16), one O(17), one O(18), one O(19), one O(3), one O(5), one O(6), and two equivalent O(2) atoms. The Ba(2)-O(14) bond length is 3.06 Å. The Ba(2)-O(16) bond length is 3.02 Å. The Ba(2)-O(17) bond length is 2.97 Å. The Ba(2)-O(18) bond length is 2.98 Å. The Ba(2)-O(19) bond length is 2.88 Å. The Ba(2)-O(3) bond length is 3.09 Å. The Ba(2)-O(5) bond length is 2.83 Å. The Ba(2)-O(6) bond length is 2.95 Å. There is one shorter (2.87 Å) and one longer (2.90 Å) Ba(2)-O(2) bond length. In the third Ba site, Ba(3) is bonded in a 10-coordinate geometry to one O(1), one O(10), one O(18), one O(19), one O(2), one O(4), one O(5), one O(6), one O(7), and one O(9) atom. The Ba(3)-O(1) bond length is 2.88 Å. The Ba(3)-O(10) bond length is 2.92 Å. The Ba(3)-O(18) bond length is 2.93 Å. The Ba(3)-O(19) bond length is 2.90 Å. The Ba(3)-O(2) bond length is 2.95 Å. The Ba(3)-O(4) bond length is 2.95 Å. The Ba(3)-O(5) bond length is 2.98 Å. The Ba(3)-O(6) bond length is 2.86 Å. The Ba(3)-O(7) bond length is 2.77 Å. The Ba(3)-O(9) bond length is 2.86 Å. In the fourth Ba site, Ba(4) is bonded in a 9-coordinate geometry to one O(11), one O(12), one O(3), one O(4), one O(5), one O(6), one O(7), and two equivalent O(8) atoms. The Ba(4)-O(11) bond length is 2.69 Å. The Ba(4)-O(12) bond length is 2.85 Å. The Ba(4)-O(3) bond length is 2.87 Å. The Ba(4)-O(4) bond length is 2.75 Å. The Ba(4)-O(5) bond length is 2.84 Å. The Ba(4)-O(6) bond length is 2.99 Å. The Ba(4)-O(7) bond length is 2.88 Å. There is one shorter (2.84 Å) and one longer (2.92 Å) Ba(4)-O(8) bond length. In the fifth Ba site, Ba(5) is bonded in a 10-coordinate geometry to one O(10), one O(12), one O(13), one O(15), one O(4), one O(7), one O(8), one O(9), and two equivalent O(11) atoms. The Ba(5)-O(10) bond length is 3.26 Å. The Ba(5)-O(12) bond length is 3.16 Å. The Ba(5)-O(13) bond length is 2.83 Å. The Ba(5)-O(15) bond length is 2.83 Å. The Ba(5)-O(4) bond length is 2.92 Å. The Ba(5)-O(7) bond length is 2.89 Å. The Ba(5)-O(8) bond length is 2.78 Å. The Ba(5)-O(9) bond length is 2.96 Å. There is one shorter (2.85 Å) and one longer (2.93 Å) Ba(5)-O(11) bond length. In the sixth Ba site, Ba(6) is bonded in a 8-coordinate geometry to one O(10), one O(12), one O(14), one O(16), one O(5), one O(6), one O(8), and one O(9) atom. The Ba(6)-O(10) bond length is 2.90 Å. The Ba(6)-O(12) bond length is 2.98 Å. The Ba(6)-O(14) bond length is 2.74 Å. The Ba(6)-O(16) bond length is 2.81 Å. The Ba(6)-O(5) bond length is 2.83 Å. The Ba(6)-O(6) bond length is 2.73 Å. The Ba(6)-O(8) bond length is 2.91 Å. The Ba(6)-O(9) bond length is 2.84 Å. In the seventh Ba site, Ba(7) is bonded in a 9-coordinate geometry to one O(10), one O(11), one O(13), one O(14), one O(15), one O(16), one O(18), one O(19), and one O(9) atom. The Ba(7)-O(10) bond length is 2.92 Å. The Ba(7)-O(11) bond length is 2.86 Å. The Ba(7)-O(13) bond length is 2.86 Å. The Ba(7)-O(14) bond length is 2.90 Å. The Ba(7)-O(15) bond length is 2.70 Å. The Ba(7)-O(16) bond length is 2.83 Å. The Ba(7)-O(18) bond length is 2.83 Å. The Ba(7)-O(19) bond length is 2.76 Å. The Ba(7)-O(9) bond length is 2.91 Å. In the eighth Ba site, Ba(8) is bonded in a 10-coordinate geometry to one O(1), one O(12), one O(13), one O(14), one O(15), one O(16), one O(2), one O(3), and two equivalent O(17) atoms. The Ba(8)-O(1) bond length is 2.78 Å. The Ba(8)-O(12) bond length is 3.07 Å. The Ba(8)-O(13) bond length is 2.81 Å. The Ba(8)-O(14) bond length is 2.99 Å. The Ba(8)-O(15) bond length is 2.95 Å. The Ba(8)-O(16) bond length is 3.06 Å. The Ba(8)-O(2) bond length is 2.85 Å. The Ba(8)-O(3) bond length is 2.81 Å. There is one shorter (2.84 Å) and one longer (2.91 Å) Ba(8)-O(17) bond length. There are eight inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(2), one O(3), one O(5), one O(6), and one O(8) atom to form a mixture of edge and corner-sharing CuO5 square pyramids. The Cu(1)-O(2) bond length is 1.83 Å. The Cu(1)-O(3) bond length is 1.88 Å. The Cu(1)-O(5) bond length is 2.22 Å. The Cu(1)-O(6) bond length is 1.95 Å. The Cu(1)-O(8) bond length is 1.95 Å. In the second Cu site, Cu(2) is bonded to one O(1), one O(3), one O(4), one O(7), and one O(8) atom to form a mixture of edge and corner-sharing CuO5 square pyramids. The Cu(2)-O(1) bond length is 1.84 Å. The Cu(2)-O(3) bond length is 1.90 Å. The Cu(2)-O(4) bond length is 1.94 Å. The Cu(2)-O(7) bond length is 2.16 Å. The Cu(2)-O(8) bond length is 1.98 Å. In the third Cu site, Cu(3) is bonded to one O(10), one O(11), one O(4), one O(7), and one O(9) atom to form corner-sharing CuO5 square pyramids. The Cu(3)-O(10) bond length is 1.93 Å. The Cu(3)-O(11) bond length is 2.20 Å. The Cu(3)-O(4) bond length is 1.95 Å. The Cu(3)-O(7) bond length is 1.84 Å. The Cu(3)-O(9) bond length is 1.97 Å. In the fourth Cu site, Cu(4) is bonded in a rectangular see-saw-like geometry to one O(10), one O(5), one O(6), and one O(9) atom. The Cu(4)-O(10) bond length is 1.87 Å. The Cu(4)-O(5) bond length is 1.82 Å. The Cu(4)-O(6) bond length is 1.89 Å. The Cu(4)-O(9) bond length is 1.93 Å. In the fifth Cu site, Cu(5) is bonded to one O(11), one O(12), one O(13), one O(15), and one O(17) atom to form CuO5 square pyramids that share  a cornercorner with one Cu(3)O5 square pyramid, corners with two equivalent Cu(8)O5 square pyramids, and  an edgeedge with one Cu(6)O4 tetrahedra. The Cu(5)-O(11) bond length is 1.85 Å. The Cu(5)-O(12) bond length is 1.94 Å. The Cu(5)-O(13) bond length is 1.96 Å. The Cu(5)-O(15) bond length is 2.18 Å. The Cu(5)-O(17) bond length is 1.98 Å. In the sixth Cu site, Cu(6) is bonded to one O(12), one O(14), one O(16), and one O(17) atom to form a mixture of distorted edge and corner-sharing CuO4 tetrahedra. The Cu(6)-O(12) bond length is 1.88 Å. The Cu(6)-O(14) bond length is 1.97 Å. The Cu(6)-O(16) bond length is 1.89 Å. The Cu(6)-O(17) bond length is 2.00 Å. In the seventh Cu site, Cu(7) is bonded to one O(14), one O(16), one O(18), one O(19), and one O(2) atom to form CuO5 square pyramids that share  a cornercorner with one Cu(1)O5 square pyramid, corners with two equivalent Cu(6)O4 tetrahedra, and  an edgeedge with one Cu(8)O5 square pyramid. The Cu(7)-O(14) bond length is 1.88 Å. The Cu(7)-O(16) bond length is 1.95 Å. The Cu(7)-O(18) bond length is 1.91 Å. The Cu(7)-O(19) bond length is 1.98 Å. The Cu(7)-O(2) bond length is 2.19 Å. In the eighth Cu site, Cu(8) is bonded to one O(1), one O(13), one O(15), one O(18), and one O(19) atom to form a mixture of edge and corner-sharing CuO5 square pyramids. The Cu(8)-O(1) bond length is 2.17 Å. The Cu(8)-O(13) bond length is 1.94 Å. The Cu(8)-O(15) bond length is 1.85 Å. The Cu(8)-O(18) bond length is 1.90 Å. The Cu(8)-O(19) bond length is 1.97 Å. There are nineteen inequivalent O sites. In the first O site, O(1) is bonded to one Ba(3), one Ba(8), two equivalent Ba(1), one Cu(2), and one Cu(8) atom to form a mixture of distorted edge, corner, and face-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 11-69°. In the second O site, O(2) is bonded in a 6-coordinate geometry to one Ba(3), one Ba(8), two equivalent Ba(2), one Cu(1), and one Cu(7) atom. In the third O site, O(3) is bonded in a distorted L-shaped geometry to one Ba(1), one Ba(2), one Ba(4), one Ba(8), one Cu(1), and one Cu(2) atom. In the fourth O site, O(4) is bonded to one Ba(1), one Ba(3), one Ba(4), one Ba(5), one Cu(2), and one Cu(3) atom to form a mixture of distorted corner and face-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 1-72°. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to one Ba(2), one Ba(3), one Ba(4), one Ba(6), one Cu(1), and one Cu(4) atom. In the sixth O site, O(6) is bonded to one Ba(2), one Ba(3), one Ba(4), one Ba(6), one Cu(1), and one Cu(4) atom to form a mixture of distorted corner and face-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 29-72°. In the seventh O site, O(7) is bonded to one Ba(1), one Ba(3), one Ba(4), one Ba(5), one Cu(2), and one Cu(3) atom to form a mixture of distorted edge, corner, and face-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 13-69°. In the eighth O site, O(8) is bonded to one Ba(5), one Ba(6), two equivalent Ba(4), one Cu(1), and one Cu(2) atom to form a mixture of distorted corner and face-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 4-62°. In the ninth O site, O(9) is bonded to one Ba(3), one Ba(5), one Ba(6), one Ba(7), one Cu(3), and one Cu(4) atom to form a mixture of distorted edge, corner, and face-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 5-66°. In the tenth O site, O(10) is bonded in a distorted L-shaped geometry to one Ba(3), one Ba(5), one Ba(6), one Ba(7), one Cu(3), and one Cu(4) atom. In the eleventh O site, O(11) is bonded in a 6-coordinate geometry to one Ba(4), one Ba(7), two equivalent Ba(5), one Cu(3), and one Cu(5) atom. In the twelfth O site, O(12) is bonded in a 2-coordinate geometry to one Ba(4), one Ba(5), one Ba(6), one Ba(8), one Cu(5), and one Cu(6) atom. In the thirteenth O site, O(13) is bonded to one Ba(1), one Ba(5), one Ba(7), one Ba(8), one Cu(5), and one Cu(8) atom to form a mixture of distorted corner and face-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 1-65°. In the fourteenth O site, O(14) is bonded in a 2-coordinate geometry to one Ba(2), one Ba(6), one Ba(7), one Ba(8), one Cu(6), and one Cu(7) atom. In the fifteenth O site, O(15) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(5), one Ba(7), one Ba(8), one Cu(5), and one Cu(8) atom. In the sixteenth O site, O(16) is bonded in a 6-coordinate geometry to one Ba(2), one Ba(6), one Ba(7), one Ba(8), one Cu(6), and one Cu(7) atom. In the seventeenth O site, O(17) is bonded to one Ba(1), one Ba(2), two equivalent Ba(8), one Cu(5), and one Cu(6) atom to form a mixture of distorted edge, corner, and face-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 3-64°. In the eighteenth O site, O(18) is bonded in a distorted L-shaped geometry to one Ba(1), one Ba(2), one Ba(3), one Ba(7), one Cu(7), and one Cu(8) atom. In the nineteenth O site, O(19) is bonded to one Ba(1), one Ba(2), one Ba(3), one Ba(7), one Cu(7), and one Cu(8) atom to form a mixture of distorted edge, corner, and face-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 5-61°.