Na7(CuO3)2 crystallizes in the monoclinic C2/c space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form a mixture of corner and edge-sharing NaO4 trigonal pyramids. In the second Na site, Na(2) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form a mixture of distorted corner and edge-sharing NaO4 trigonal pyramids. In the third Na site, Na(3) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(2), and two equivalent O(3) atoms. In the fourth Na site, Na(4) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form a mixture of distorted corner and edge-sharing NaO4 trigonal pyramids. Cu(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Na(2), one Na(3), one Na(4), two equivalent Na(1), and one Cu(1) atom to form a mixture of distorted corner, face, and edge-sharing ONa5Cu octahedra. The corner-sharing octahedral tilt angles range from 49-58°. In the second O site, O(2) is bonded to one Na(1), one Na(2), one Na(4), two equivalent Na(3), and one Cu(1) atom to form a mixture of distorted corner and edge-sharing ONa5Cu octahedra. The corner-sharing octahedral tilt angles range from 39-60°. In the third O site, O(3) is bonded in a 6-coordinate geometry to one Na(1), two equivalent Na(2), two equivalent Na(3), and one Cu(1) atom.
Na7(CuO3)2 crystallizes in the monoclinic C2/c space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form a mixture of corner and edge-sharing NaO4 trigonal pyramids. The Na(1)-O(2) bond length is 2.29 Å. The Na(1)-O(3) bond length is 2.27 Å. There is one shorter (2.36 Å) and one longer (2.42 Å) Na(1)-O(1) bond length. In the second Na site, Na(2) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form a mixture of distorted corner and edge-sharing NaO4 trigonal pyramids. The Na(2)-O(1) bond length is 2.32 Å. The Na(2)-O(2) bond length is 2.36 Å. There is one shorter (2.30 Å) and one longer (2.33 Å) Na(2)-O(3) bond length. In the third Na site, Na(3) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(2), and two equivalent O(3) atoms. The Na(3)-O(1) bond length is 2.42 Å. There is one shorter (2.42 Å) and one longer (2.50 Å) Na(3)-O(2) bond length. There is one shorter (2.43 Å) and one longer (2.67 Å) Na(3)-O(3) bond length. In the fourth Na site, Na(4) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form a mixture of distorted corner and edge-sharing NaO4 trigonal pyramids. Both Na(4)-O(1) bond lengths are 2.40 Å. Both Na(4)-O(2) bond lengths are 2.34 Å. Cu(1) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(3) atom. The Cu(1)-O(1) bond length is 1.84 Å. The Cu(1)-O(2) bond length is 1.85 Å. The Cu(1)-O(3) bond length is 1.86 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Na(2), one Na(3), one Na(4), two equivalent Na(1), and one Cu(1) atom to form a mixture of distorted corner, face, and edge-sharing ONa5Cu octahedra. The corner-sharing octahedral tilt angles range from 49-58°. In the second O site, O(2) is bonded to one Na(1), one Na(2), one Na(4), two equivalent Na(3), and one Cu(1) atom to form a mixture of distorted corner and edge-sharing ONa5Cu octahedra. The corner-sharing octahedral tilt angles range from 39-60°. In the third O site, O(3) is bonded in a 6-coordinate geometry to one Na(1), two equivalent Na(2), two equivalent Na(3), and one Cu(1) atom.