Na3(CoO2)4 crystallizes in the triclinic P-1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to two equivalent O(3) and two equivalent O(4) atoms. There are three inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(3), one O(4), and two equivalent O(2) atoms to form edge-sharing CoO5 trigonal bipyramids. In the second Co site, Co(2) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(3) atoms. In the third Co site, Co(3) is bonded in a square co-planar geometry to two equivalent O(3) and two equivalent O(4) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Na(1), one Co(1), and one Co(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Na(1) and two equivalent Co(1) atoms. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Na(1), one Na(2), one Co(1), one Co(2), and one Co(3) atom. In the fourth O site, O(4) is bonded to one Na(2), two equivalent Na(1), one Co(1), and one Co(3) atom to form a mixture of distorted edge and corner-sharing ONa3Co2 trigonal bipyramids.
Na3(CoO2)4 crystallizes in the triclinic P-1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms. The Na(1)-O(2) bond length is 2.27 Å. The Na(1)-O(3) bond length is 2.63 Å. There is one shorter (2.24 Å) and one longer (2.48 Å) Na(1)-O(1) bond length. There is one shorter (2.38 Å) and one longer (2.47 Å) Na(1)-O(4) bond length. In the second Na site, Na(2) is bonded in a 4-coordinate geometry to two equivalent O(3) and two equivalent O(4) atoms. Both Na(2)-O(3) bond lengths are 2.39 Å. Both Na(2)-O(4) bond lengths are 2.41 Å. There are three inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(3), one O(4), and two equivalent O(2) atoms to form edge-sharing CoO5 trigonal bipyramids. The Co(1)-O(1) bond length is 1.93 Å. The Co(1)-O(3) bond length is 2.13 Å. The Co(1)-O(4) bond length is 1.90 Å. There is one shorter (1.83 Å) and one longer (1.96 Å) Co(1)-O(2) bond length. In the second Co site, Co(2) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(3) atoms. Both Co(2)-O(1) bond lengths are 1.82 Å. Both Co(2)-O(3) bond lengths are 1.95 Å. In the third Co site, Co(3) is bonded in a square co-planar geometry to two equivalent O(3) and two equivalent O(4) atoms. Both Co(3)-O(3) bond lengths are 2.01 Å. Both Co(3)-O(4) bond lengths are 1.86 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Na(1), one Co(1), and one Co(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Na(1) and two equivalent Co(1) atoms. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Na(1), one Na(2), one Co(1), one Co(2), and one Co(3) atom. In the fourth O site, O(4) is bonded to one Na(2), two equivalent Na(1), one Co(1), and one Co(3) atom to form a mixture of distorted edge and corner-sharing ONa3Co2 trigonal bipyramids.