Na3CuO2 crystallizes in the orthorhombic Ibam space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to four equivalent O(1) atoms to form a mixture of distorted edge and corner-sharing NaO4 tetrahedra. In the second Na site, Na(2) is bonded to four equivalent O(1) atoms to form a mixture of edge and corner-sharing NaO4 tetrahedra. Cu(1) is bonded in a linear geometry to two equivalent O(1) atoms. O(1) is bonded in a 7-coordinate geometry to two equivalent Na(2), four equivalent Na(1), and one Cu(1) atom.
Na3CuO2 crystallizes in the orthorhombic Ibam space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to four equivalent O(1) atoms to form a mixture of distorted edge and corner-sharing NaO4 tetrahedra. There are two shorter (2.34 Å) and two longer (2.49 Å) Na(1)-O(1) bond lengths. In the second Na site, Na(2) is bonded to four equivalent O(1) atoms to form a mixture of edge and corner-sharing NaO4 tetrahedra. All Na(2)-O(1) bond lengths are 2.40 Å. Cu(1) is bonded in a linear geometry to two equivalent O(1) atoms. Both Cu(1)-O(1) bond lengths are 1.88 Å. O(1) is bonded in a 7-coordinate geometry to two equivalent Na(2), four equivalent Na(1), and one Cu(1) atom.