NaCoO2 crystallizes in the triclinic P1 space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent O(3), two equivalent O(5), and two equivalent O(8) atoms to form NaO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Co(1)O5 square pyramids, corners with two equivalent Co(2)O5 square pyramids, corners with two equivalent Co(3)O5 square pyramids, edges with two equivalent Na(1)O6 octahedra, edges with four equivalent Na(4)O6 octahedra,  an edgeedge with one Co(1)O5 square pyramid,  an edgeedge with one Co(3)O5 square pyramid, and edges with two equivalent Co(2)O5 square pyramids. The corner-sharing octahedral tilt angles are 14°. In the second Na site, Na(2) is bonded to two equivalent O(4), two equivalent O(6), and two equivalent O(7) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Co(1)O5 square pyramids, corners with two equivalent Co(3)O5 square pyramids, corners with two equivalent Co(4)O5 square pyramids, edges with two equivalent Na(2)O6 octahedra, edges with four equivalent Na(3)O6 octahedra,  an edgeedge with one Co(1)O5 square pyramid,  an edgeedge with one Co(3)O5 square pyramid, and edges with two equivalent Co(4)O5 square pyramids. The corner-sharing octahedral tilt angles are 15°. In the third Na site, Na(3) is bonded to two equivalent O(1), two equivalent O(6), and two equivalent O(7) atoms to form NaO6 octahedra that share corners with two equivalent Na(3)O6 octahedra, corners with two equivalent Co(2)O5 square pyramids, corners with two equivalent Co(3)O5 square pyramids, corners with two equivalent Co(4)O5 square pyramids, edges with two equivalent Na(3)O6 octahedra, edges with four equivalent Na(2)O6 octahedra,  an edgeedge with one Co(2)O5 square pyramid,  an edgeedge with one Co(4)O5 square pyramid, and edges with two equivalent Co(3)O5 square pyramids. The corner-sharing octahedral tilt angles are 14°. In the fourth Na site, Na(4) is bonded to two equivalent O(2), two equivalent O(5), and two equivalent O(8) atoms to form NaO6 octahedra that share corners with two equivalent Na(4)O6 octahedra, corners with two equivalent Co(1)O5 square pyramids, corners with two equivalent Co(2)O5 square pyramids, corners with two equivalent Co(4)O5 square pyramids, edges with two equivalent Na(4)O6 octahedra, edges with four equivalent Na(1)O6 octahedra,  an edgeedge with one Co(2)O5 square pyramid,  an edgeedge with one Co(4)O5 square pyramid, and edges with two equivalent Co(1)O5 square pyramids. The corner-sharing octahedral tilt angles are 15°. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(2), two equivalent O(4), and two equivalent O(8) atoms to form CoO5 square pyramids that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Na(4)O6 octahedra, corners with four equivalent Co(4)O5 square pyramids,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, and edges with two equivalent Co(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 11-83°. In the second Co site, Co(2) is bonded to one O(3), two equivalent O(1), and two equivalent O(5) atoms to form distorted CoO5 square pyramids that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(3)O6 octahedra, corners with two equivalent Na(4)O6 octahedra, corners with four equivalent Co(3)O5 square pyramids,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, and edges with two equivalent Co(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 8-83°. In the third Co site, Co(3) is bonded to one O(1), two equivalent O(3), and two equivalent O(7) atoms to form distorted CoO5 square pyramids that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Na(3)O6 octahedra, corners with four equivalent Co(2)O5 square pyramids,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, and edges with two equivalent Co(3)O5 square pyramids. The corner-sharing octahedral tilt angles range from 9-84°. In the fourth Co site, Co(4) is bonded to one O(4), two equivalent O(2), and two equivalent O(6) atoms to form distorted CoO5 square pyramids that share corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Na(3)O6 octahedra, corners with two equivalent Na(4)O6 octahedra, corners with four equivalent Co(1)O5 square pyramids,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, and edges with two equivalent Co(4)O5 square pyramids. The corner-sharing octahedral tilt angles range from 6-87°. There are eight inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Na(3), one Co(3), and two equivalent Co(2) atoms to form distorted ONa2Co3 square pyramids that share corners with two equivalent O(5)Na4Co2 octahedra, corners with two equivalent O(6)Na4Co2 octahedra, corners with two equivalent O(7)Na4Co2 octahedra, corners with four equivalent O(3)Na2Co3 square pyramids,  an edgeedge with one O(5)Na4Co2 octahedra,  an edgeedge with one O(6)Na4Co2 octahedra, edges with two equivalent O(7)Na4Co2 octahedra, and edges with two equivalent O(1)Na2Co3 square pyramids. The corner-sharing octahedral tilt angles range from 8-89°. In the second O site, O(2) is bonded in a 5-coordinate geometry to two equivalent Na(4), one Co(1), and two equivalent Co(4) atoms. In the third O site, O(3) is bonded to two equivalent Na(1), one Co(2), and two equivalent Co(3) atoms to form distorted ONa2Co3 square pyramids that share corners with two equivalent O(5)Na4Co2 octahedra, corners with two equivalent O(7)Na4Co2 octahedra, corners with two equivalent O(8)Na4Co2 octahedra, corners with four equivalent O(1)Na2Co3 square pyramids,  an edgeedge with one O(7)Na4Co2 octahedra,  an edgeedge with one O(8)Na4Co2 octahedra, edges with two equivalent O(5)Na4Co2 octahedra, and edges with two equivalent O(3)Na2Co3 square pyramids. The corner-sharing octahedral tilt angles range from 9-88°. In the fourth O site, O(4) is bonded to two equivalent Na(2), one Co(4), and two equivalent Co(1) atoms to form distorted ONa2Co3 square pyramids that share corners with two equivalent O(6)Na4Co2 octahedra, corners with two equivalent O(7)Na4Co2 octahedra, corners with two equivalent O(8)Na4Co2 octahedra,  an edgeedge with one O(7)Na4Co2 octahedra,  an edgeedge with one O(8)Na4Co2 octahedra, edges with two equivalent O(6)Na4Co2 octahedra, and edges with two equivalent O(4)Na2Co3 square pyramids. The corner-sharing octahedral tilt angles range from 8-90°. In the fifth O site, O(5) is bonded to two equivalent Na(1), two equivalent Na(4), and two equivalent Co(2) atoms to form distorted ONa4Co2 octahedra that share corners with two equivalent O(5)Na4Co2 octahedra, corners with two equivalent O(1)Na2Co3 square pyramids, corners with two equivalent O(3)Na2Co3 square pyramids, edges with two equivalent O(5)Na4Co2 octahedra, edges with four equivalent O(8)Na4Co2 octahedra,  an edgeedge with one O(1)Na2Co3 square pyramid, and edges with two equivalent O(3)Na2Co3 square pyramids. The corner-sharing octahedral tilt angles are 14°. In the sixth O site, O(6) is bonded to two equivalent Na(2), two equivalent Na(3), and two equivalent Co(4) atoms to form ONa4Co2 octahedra that share corners with two equivalent O(6)Na4Co2 octahedra, corners with two equivalent O(1)Na2Co3 square pyramids, corners with two equivalent O(4)Na2Co3 square pyramids, edges with two equivalent O(6)Na4Co2 octahedra, edges with four equivalent O(7)Na4Co2 octahedra,  an edgeedge with one O(1)Na2Co3 square pyramid, and edges with two equivalent O(4)Na2Co3 square pyramids. The corner-sharing octahedral tilt angles are 15°. In the seventh O site, O(7) is bonded to two equivalent Na(2), two equivalent Na(3), and two equivalent Co(3) atoms to form distorted ONa4Co2 octahedra that share corners with two equivalent O(7)Na4Co2 octahedra, corners with two equivalent O(1)Na2Co3 square pyramids, corners with two equivalent O(3)Na2Co3 square pyramids, corners with two equivalent O(4)Na2Co3 square pyramids, edges with two equivalent O(7)Na4Co2 octahedra, edges with four equivalent O(6)Na4Co2 octahedra,  an edgeedge with one O(3)Na2Co3 square pyramid,  an edgeedge with one O(4)Na2Co3 square pyramid, and edges with two equivalent O(1)Na2Co3 square pyramids. The corner-sharing octahedral tilt angles are 14°. In the eighth O site, O(8) is bonded to two equivalent Na(1), two equivalent Na(4), and two equivalent Co(1) atoms to form ONa4Co2 octahedra that share corners with two equivalent O(8)Na4Co2 octahedra, corners with two equivalent O(3)Na2Co3 square pyramids, corners with two equivalent O(4)Na2Co3 square pyramids, edges with two equivalent O(8)Na4Co2 octahedra, edges with four equivalent O(5)Na4Co2 octahedra,  an edgeedge with one O(3)Na2Co3 square pyramid, and  an edgeedge with one O(4)Na2Co3 square pyramid. The corner-sharing octahedral tilt angles are 15°.
NaCoO2 crystallizes in the triclinic P1 space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded to two equivalent O(3), two equivalent O(5), and two equivalent O(8) atoms to form NaO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Co(1)O5 square pyramids, corners with two equivalent Co(2)O5 square pyramids, corners with two equivalent Co(3)O5 square pyramids, edges with two equivalent Na(1)O6 octahedra, edges with four equivalent Na(4)O6 octahedra,  an edgeedge with one Co(1)O5 square pyramid,  an edgeedge with one Co(3)O5 square pyramid, and edges with two equivalent Co(2)O5 square pyramids. The corner-sharing octahedral tilt angles are 14°. There is one shorter (2.38 Å) and one longer (2.43 Å) Na(1)-O(3) bond length. There is one shorter (2.41 Å) and one longer (2.47 Å) Na(1)-O(5) bond length. There is one shorter (2.36 Å) and one longer (2.45 Å) Na(1)-O(8) bond length. In the second Na site, Na(2) is bonded to two equivalent O(4), two equivalent O(6), and two equivalent O(7) atoms to form distorted NaO6 octahedra that share corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Co(1)O5 square pyramids, corners with two equivalent Co(3)O5 square pyramids, corners with two equivalent Co(4)O5 square pyramids, edges with two equivalent Na(2)O6 octahedra, edges with four equivalent Na(3)O6 octahedra,  an edgeedge with one Co(1)O5 square pyramid,  an edgeedge with one Co(3)O5 square pyramid, and edges with two equivalent Co(4)O5 square pyramids. The corner-sharing octahedral tilt angles are 15°. There is one shorter (2.37 Å) and one longer (2.46 Å) Na(2)-O(4) bond length. There is one shorter (2.43 Å) and one longer (2.46 Å) Na(2)-O(6) bond length. There is one shorter (2.36 Å) and one longer (2.40 Å) Na(2)-O(7) bond length. In the third Na site, Na(3) is bonded to two equivalent O(1), two equivalent O(6), and two equivalent O(7) atoms to form NaO6 octahedra that share corners with two equivalent Na(3)O6 octahedra, corners with two equivalent Co(2)O5 square pyramids, corners with two equivalent Co(3)O5 square pyramids, corners with two equivalent Co(4)O5 square pyramids, edges with two equivalent Na(3)O6 octahedra, edges with four equivalent Na(2)O6 octahedra,  an edgeedge with one Co(2)O5 square pyramid,  an edgeedge with one Co(4)O5 square pyramid, and edges with two equivalent Co(3)O5 square pyramids. The corner-sharing octahedral tilt angles are 14°. There is one shorter (2.40 Å) and one longer (2.41 Å) Na(3)-O(1) bond length. Both Na(3)-O(6) bond lengths are 2.37 Å. There is one shorter (2.41 Å) and one longer (2.47 Å) Na(3)-O(7) bond length. In the fourth Na site, Na(4) is bonded to two equivalent O(2), two equivalent O(5), and two equivalent O(8) atoms to form NaO6 octahedra that share corners with two equivalent Na(4)O6 octahedra, corners with two equivalent Co(1)O5 square pyramids, corners with two equivalent Co(2)O5 square pyramids, corners with two equivalent Co(4)O5 square pyramids, edges with two equivalent Na(4)O6 octahedra, edges with four equivalent Na(1)O6 octahedra,  an edgeedge with one Co(2)O5 square pyramid,  an edgeedge with one Co(4)O5 square pyramid, and edges with two equivalent Co(1)O5 square pyramids. The corner-sharing octahedral tilt angles are 15°. There is one shorter (2.35 Å) and one longer (2.39 Å) Na(4)-O(2) bond length. There is one shorter (2.35 Å) and one longer (2.39 Å) Na(4)-O(5) bond length. There is one shorter (2.44 Å) and one longer (2.45 Å) Na(4)-O(8) bond length. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(2), two equivalent O(4), and two equivalent O(8) atoms to form CoO5 square pyramids that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Na(4)O6 octahedra, corners with four equivalent Co(4)O5 square pyramids,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, and edges with two equivalent Co(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 11-83°. The Co(1)-O(2) bond length is 2.08 Å. There is one shorter (1.94 Å) and one longer (1.96 Å) Co(1)-O(4) bond length. There is one shorter (1.90 Å) and one longer (1.94 Å) Co(1)-O(8) bond length. In the second Co site, Co(2) is bonded to one O(3), two equivalent O(1), and two equivalent O(5) atoms to form distorted CoO5 square pyramids that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(3)O6 octahedra, corners with two equivalent Na(4)O6 octahedra, corners with four equivalent Co(3)O5 square pyramids,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, and edges with two equivalent Co(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 8-83°. The Co(2)-O(3) bond length is 1.98 Å. There is one shorter (1.90 Å) and one longer (2.14 Å) Co(2)-O(1) bond length. There is one shorter (1.84 Å) and one longer (2.10 Å) Co(2)-O(5) bond length. In the third Co site, Co(3) is bonded to one O(1), two equivalent O(3), and two equivalent O(7) atoms to form distorted CoO5 square pyramids that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Na(3)O6 octahedra, corners with four equivalent Co(2)O5 square pyramids,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, and edges with two equivalent Co(3)O5 square pyramids. The corner-sharing octahedral tilt angles range from 9-84°. The Co(3)-O(1) bond length is 1.98 Å. There is one shorter (1.90 Å) and one longer (2.14 Å) Co(3)-O(3) bond length. There is one shorter (1.83 Å) and one longer (2.12 Å) Co(3)-O(7) bond length. In the fourth Co site, Co(4) is bonded to one O(4), two equivalent O(2), and two equivalent O(6) atoms to form distorted CoO5 square pyramids that share corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Na(3)O6 octahedra, corners with two equivalent Na(4)O6 octahedra, corners with four equivalent Co(1)O5 square pyramids,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, and edges with two equivalent Co(4)O5 square pyramids. The corner-sharing octahedral tilt angles range from 6-87°. The Co(4)-O(4) bond length is 2.05 Å. There is one shorter (1.89 Å) and one longer (2.10 Å) Co(4)-O(2) bond length. There is one shorter (1.84 Å) and one longer (2.13 Å) Co(4)-O(6) bond length. There are eight inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Na(3), one Co(3), and two equivalent Co(2) atoms to form distorted ONa2Co3 square pyramids that share corners with two equivalent O(5)Na4Co2 octahedra, corners with two equivalent O(6)Na4Co2 octahedra, corners with two equivalent O(7)Na4Co2 octahedra, corners with four equivalent O(3)Na2Co3 square pyramids,  an edgeedge with one O(5)Na4Co2 octahedra,  an edgeedge with one O(6)Na4Co2 octahedra, edges with two equivalent O(7)Na4Co2 octahedra, and edges with two equivalent O(1)Na2Co3 square pyramids. The corner-sharing octahedral tilt angles range from 8-89°. In the second O site, O(2) is bonded in a 5-coordinate geometry to two equivalent Na(4), one Co(1), and two equivalent Co(4) atoms. In the third O site, O(3) is bonded to two equivalent Na(1), one Co(2), and two equivalent Co(3) atoms to form distorted ONa2Co3 square pyramids that share corners with two equivalent O(5)Na4Co2 octahedra, corners with two equivalent O(7)Na4Co2 octahedra, corners with two equivalent O(8)Na4Co2 octahedra, corners with four equivalent O(1)Na2Co3 square pyramids,  an edgeedge with one O(7)Na4Co2 octahedra,  an edgeedge with one O(8)Na4Co2 octahedra, edges with two equivalent O(5)Na4Co2 octahedra, and edges with two equivalent O(3)Na2Co3 square pyramids. The corner-sharing octahedral tilt angles range from 9-88°. In the fourth O site, O(4) is bonded to two equivalent Na(2), one Co(4), and two equivalent Co(1) atoms to form distorted ONa2Co3 square pyramids that share corners with two equivalent O(6)Na4Co2 octahedra, corners with two equivalent O(7)Na4Co2 octahedra, corners with two equivalent O(8)Na4Co2 octahedra,  an edgeedge with one O(7)Na4Co2 octahedra,  an edgeedge with one O(8)Na4Co2 octahedra, edges with two equivalent O(6)Na4Co2 octahedra, and edges with two equivalent O(4)Na2Co3 square pyramids. The corner-sharing octahedral tilt angles range from 8-90°. In the fifth O site, O(5) is bonded to two equivalent Na(1), two equivalent Na(4), and two equivalent Co(2) atoms to form distorted ONa4Co2 octahedra that share corners with two equivalent O(5)Na4Co2 octahedra, corners with two equivalent O(1)Na2Co3 square pyramids, corners with two equivalent O(3)Na2Co3 square pyramids, edges with two equivalent O(5)Na4Co2 octahedra, edges with four equivalent O(8)Na4Co2 octahedra,  an edgeedge with one O(1)Na2Co3 square pyramid, and edges with two equivalent O(3)Na2Co3 square pyramids. The corner-sharing octahedral tilt angles are 14°. In the sixth O site, O(6) is bonded to two equivalent Na(2), two equivalent Na(3), and two equivalent Co(4) atoms to form ONa4Co2 octahedra that share corners with two equivalent O(6)Na4Co2 octahedra, corners with two equivalent O(1)Na2Co3 square pyramids, corners with two equivalent O(4)Na2Co3 square pyramids, edges with two equivalent O(6)Na4Co2 octahedra, edges with four equivalent O(7)Na4Co2 octahedra,  an edgeedge with one O(1)Na2Co3 square pyramid, and edges with two equivalent O(4)Na2Co3 square pyramids. The corner-sharing octahedral tilt angles are 15°. In the seventh O site, O(7) is bonded to two equivalent Na(2), two equivalent Na(3), and two equivalent Co(3) atoms to form distorted ONa4Co2 octahedra that share corners with two equivalent O(7)Na4Co2 octahedra, corners with two equivalent O(1)Na2Co3 square pyramids, corners with two equivalent O(3)Na2Co3 square pyramids, corners with two equivalent O(4)Na2Co3 square pyramids, edges with two equivalent O(7)Na4Co2 octahedra, edges with four equivalent O(6)Na4Co2 octahedra,  an edgeedge with one O(3)Na2Co3 square pyramid,  an edgeedge with one O(4)Na2Co3 square pyramid, and edges with two equivalent O(1)Na2Co3 square pyramids. The corner-sharing octahedral tilt angles are 14°. In the eighth O site, O(8) is bonded to two equivalent Na(1), two equivalent Na(4), and two equivalent Co(1) atoms to form ONa4Co2 octahedra that share corners with two equivalent O(8)Na4Co2 octahedra, corners with two equivalent O(3)Na2Co3 square pyramids, corners with two equivalent O(4)Na2Co3 square pyramids, edges with two equivalent O(8)Na4Co2 octahedra, edges with four equivalent O(5)Na4Co2 octahedra,  an edgeedge with one O(3)Na2Co3 square pyramid, and  an edgeedge with one O(4)Na2Co3 square pyramid. The corner-sharing octahedral tilt angles are 15°.