Cu9O13 crystallizes in the monoclinic C2/m space group. There are five inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to two equivalent O(6) and four equivalent O(7) atoms to form a mixture of corner and edge-sharing CuO6 octahedra. The corner-sharing octahedral tilt angles are 14°. In the second Cu site, Cu(2) is bonded to one O(4), two equivalent O(1), and three equivalent O(3) atoms to form a mixture of corner and edge-sharing CuO6 octahedra. The corner-sharing octahedral tilt angles range from 0-14°. In the third Cu site, Cu(3) is bonded to one O(5), two equivalent O(6), and three equivalent O(7) atoms to form a mixture of corner and edge-sharing CuO6 octahedra. The corner-sharing octahedral tilt angles are 14°. In the fourth Cu site, Cu(4) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form a mixture of distorted corner and edge-sharing CuO6 octahedra. The corner-sharing octahedral tilt angles range from 0-14°. In the fifth Cu site, Cu(5) is bonded in a 6-coordinate geometry to one O(2), one O(7), two equivalent O(5), and two equivalent O(6) atoms. There are seven inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Cu(4) and four equivalent Cu(2) atoms to form OCu6 octahedra that share corners with four equivalent O(3)Cu5 square pyramids, edges with two equivalent O(1)Cu6 octahedra, and edges with six equivalent O(3)Cu5 square pyramids. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Cu(4) and one Cu(5) atom. In the third O site, O(3) is bonded to two equivalent Cu(4) and three equivalent Cu(2) atoms to form OCu5 square pyramids that share corners with two equivalent O(1)Cu6 octahedra, edges with three equivalent O(1)Cu6 octahedra, and edges with four equivalent O(3)Cu5 square pyramids. The corner-sharing octahedral tilt angles are 7°. In the fourth O site, O(4) is bonded in a trigonal non-coplanar geometry to one Cu(2) and two equivalent Cu(4) atoms. In the fifth O site, O(5) is bonded in a trigonal non-coplanar geometry to one Cu(3) and two equivalent Cu(5) atoms. In the sixth O site, O(6) is bonded to one Cu(1), two equivalent Cu(3), and two equivalent Cu(5) atoms to form OCu5 square pyramids that share corners with two equivalent O(7)Cu6 octahedra,  a cornercorner with one O(6)Cu5 square pyramid, edges with five equivalent O(7)Cu6 octahedra, and edges with two equivalent O(6)Cu5 square pyramids. The corner-sharing octahedral tilt angles are 13°. In the seventh O site, O(7) is bonded to one Cu(5), two equivalent Cu(1), and three equivalent Cu(3) atoms to form distorted OCu6 octahedra that share corners with two equivalent O(7)Cu6 octahedra, corners with two equivalent O(6)Cu5 square pyramids, edges with five equivalent O(7)Cu6 octahedra, and edges with five equivalent O(6)Cu5 square pyramids. The corner-sharing octahedra are not tilted.
Cu9O13 crystallizes in the monoclinic C2/m space group. There are five inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to two equivalent O(6) and four equivalent O(7) atoms to form a mixture of corner and edge-sharing CuO6 octahedra. The corner-sharing octahedral tilt angles are 14°. Both Cu(1)-O(6) bond lengths are 1.94 Å. All Cu(1)-O(7) bond lengths are 2.07 Å. In the second Cu site, Cu(2) is bonded to one O(4), two equivalent O(1), and three equivalent O(3) atoms to form a mixture of corner and edge-sharing CuO6 octahedra. The corner-sharing octahedral tilt angles range from 0-14°. The Cu(2)-O(4) bond length is 1.85 Å. Both Cu(2)-O(1) bond lengths are 2.10 Å. There is one shorter (1.93 Å) and two longer (2.11 Å) Cu(2)-O(3) bond lengths. In the third Cu site, Cu(3) is bonded to one O(5), two equivalent O(6), and three equivalent O(7) atoms to form a mixture of corner and edge-sharing CuO6 octahedra. The corner-sharing octahedral tilt angles are 14°. The Cu(3)-O(5) bond length is 1.84 Å. Both Cu(3)-O(6) bond lengths are 2.14 Å. There is one shorter (1.95 Å) and two longer (2.14 Å) Cu(3)-O(7) bond lengths. In the fourth Cu site, Cu(4) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form a mixture of distorted corner and edge-sharing CuO6 octahedra. The corner-sharing octahedral tilt angles range from 0-14°. The Cu(4)-O(1) bond length is 2.18 Å. The Cu(4)-O(2) bond length is 1.83 Å. Both Cu(4)-O(3) bond lengths are 2.11 Å. Both Cu(4)-O(4) bond lengths are 1.93 Å. In the fifth Cu site, Cu(5) is bonded in a 6-coordinate geometry to one O(2), one O(7), two equivalent O(5), and two equivalent O(6) atoms. The Cu(5)-O(2) bond length is 1.86 Å. The Cu(5)-O(7) bond length is 2.52 Å. Both Cu(5)-O(5) bond lengths are 1.92 Å. Both Cu(5)-O(6) bond lengths are 2.09 Å. There are seven inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Cu(4) and four equivalent Cu(2) atoms to form OCu6 octahedra that share corners with four equivalent O(3)Cu5 square pyramids, edges with two equivalent O(1)Cu6 octahedra, and edges with six equivalent O(3)Cu5 square pyramids. In the second O site, O(2) is bonded in a bent 120 degrees geometry to one Cu(4) and one Cu(5) atom. In the third O site, O(3) is bonded to two equivalent Cu(4) and three equivalent Cu(2) atoms to form OCu5 square pyramids that share corners with two equivalent O(1)Cu6 octahedra, edges with three equivalent O(1)Cu6 octahedra, and edges with four equivalent O(3)Cu5 square pyramids. The corner-sharing octahedral tilt angles are 7°. In the fourth O site, O(4) is bonded in a trigonal non-coplanar geometry to one Cu(2) and two equivalent Cu(4) atoms. In the fifth O site, O(5) is bonded in a trigonal non-coplanar geometry to one Cu(3) and two equivalent Cu(5) atoms. In the sixth O site, O(6) is bonded to one Cu(1), two equivalent Cu(3), and two equivalent Cu(5) atoms to form OCu5 square pyramids that share corners with two equivalent O(7)Cu6 octahedra,  a cornercorner with one O(6)Cu5 square pyramid, edges with five equivalent O(7)Cu6 octahedra, and edges with two equivalent O(6)Cu5 square pyramids. The corner-sharing octahedral tilt angles are 13°. In the seventh O site, O(7) is bonded to one Cu(5), two equivalent Cu(1), and three equivalent Cu(3) atoms to form distorted OCu6 octahedra that share corners with two equivalent O(7)Cu6 octahedra, corners with two equivalent O(6)Cu5 square pyramids, edges with five equivalent O(7)Cu6 octahedra, and edges with five equivalent O(6)Cu5 square pyramids. The corner-sharing octahedra are not tilted.