Na3CoO3 crystallizes in the tetragonal P4_2/mnm space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to one O(1) and four equivalent O(2) atoms. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to two equivalent O(1) and two equivalent O(2) atoms. Co(1) is bonded in a rectangular see-saw-like geometry to two equivalent O(1) and two equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Na(1), two equivalent Na(2), and two equivalent Co(1) atoms to form a mixture of distorted corner and edge-sharing ONa4Co2 octahedra. The corner-sharing octahedral tilt angles are 32°. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Na(2), four equivalent Na(1), and one Co(1) atom.
Na3CoO3 crystallizes in the tetragonal P4_2/mnm space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to one O(1) and four equivalent O(2) atoms. The Na(1)-O(1) bond length is 2.55 Å. There are a spread of Na(1)-O(2) bond distances ranging from 2.22-2.94 Å. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to two equivalent O(1) and two equivalent O(2) atoms. Both Na(2)-O(1) bond lengths are 2.34 Å. Both Na(2)-O(2) bond lengths are 2.33 Å. Co(1) is bonded in a rectangular see-saw-like geometry to two equivalent O(1) and two equivalent O(2) atoms. Both Co(1)-O(1) bond lengths are 1.93 Å. Both Co(1)-O(2) bond lengths are 1.79 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Na(1), two equivalent Na(2), and two equivalent Co(1) atoms to form a mixture of distorted corner and edge-sharing ONa4Co2 octahedra. The corner-sharing octahedral tilt angles are 32°. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Na(2), four equivalent Na(1), and one Co(1) atom.