Na3CoO3 crystallizes in the monoclinic P2_1/c space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to one O(3), two equivalent O(1), and two equivalent O(2) atoms. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to one O(1), two equivalent O(2), and two equivalent O(3) atoms. In the third Na site, Na(3) is bonded in a 4-coordinate geometry to one O(1), one O(3), and two equivalent O(2) atoms. Co(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form distorted edge-sharing CoO4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to one Na(2), one Na(3), two equivalent Na(1), and two equivalent Co(1) atoms. In the second O site, O(2) is bonded in a 7-coordinate geometry to two equivalent Na(1), two equivalent Na(2), two equivalent Na(3), and one Co(1) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Na(1), one Na(3), two equivalent Na(2), and one Co(1) atom.
Na3CoO3 crystallizes in the monoclinic P2_1/c space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to one O(3), two equivalent O(1), and two equivalent O(2) atoms. The Na(1)-O(3) bond length is 2.45 Å. There is one shorter (2.30 Å) and one longer (2.63 Å) Na(1)-O(1) bond length. There is one shorter (2.31 Å) and one longer (2.73 Å) Na(1)-O(2) bond length. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to one O(1), two equivalent O(2), and two equivalent O(3) atoms. The Na(2)-O(1) bond length is 2.34 Å. There is one shorter (2.40 Å) and one longer (2.80 Å) Na(2)-O(2) bond length. There is one shorter (2.20 Å) and one longer (2.39 Å) Na(2)-O(3) bond length. In the third Na site, Na(3) is bonded in a 4-coordinate geometry to one O(1), one O(3), and two equivalent O(2) atoms. The Na(3)-O(1) bond length is 2.35 Å. The Na(3)-O(3) bond length is 2.36 Å. There is one shorter (2.31 Å) and one longer (2.49 Å) Na(3)-O(2) bond length. Co(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form distorted edge-sharing CoO4 tetrahedra. The Co(1)-O(2) bond length is 1.79 Å. The Co(1)-O(3) bond length is 1.78 Å. Both Co(1)-O(1) bond lengths are 1.95 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to one Na(2), one Na(3), two equivalent Na(1), and two equivalent Co(1) atoms. In the second O site, O(2) is bonded in a 7-coordinate geometry to two equivalent Na(1), two equivalent Na(2), two equivalent Na(3), and one Co(1) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Na(1), one Na(3), two equivalent Na(2), and one Co(1) atom.