Na5(NiO2)6 crystallizes in the triclinic P-1 space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1), one O(2), one O(5), one O(6), and two equivalent O(4) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Ni(3)O6 octahedra, corners with two equivalent Ni(2)O6 octahedra, corners with three equivalent Ni(1)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, edges with two equivalent Ni(3)O6 octahedra, and edges with three equivalent Na(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-17°. In the second Na site, Na(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms to form distorted NaO6 octahedra that share corners with two equivalent Ni(1)O6 octahedra, corners with four equivalent Ni(3)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, and edges with two equivalent Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 12-17°. In the third Na site, Na(3) is bonded to one O(3), one O(4), one O(5), one O(6), and two equivalent O(1) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Ni(3)O6 octahedra, corners with two equivalent Ni(1)O6 octahedra, corners with three equivalent Ni(2)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Na(3)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, edges with two equivalent Ni(3)O6 octahedra, and edges with three equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-18°. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(2), one O(4), one O(6), and two equivalent O(5) atoms to form NiO6 octahedra that share  a cornercorner with one Na(2)O6 octahedra, corners with two equivalent Na(3)O6 octahedra, corners with three equivalent Na(1)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Ni(1)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Ni(3)O6 octahedra, and edges with three equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-17°. In the second Ni site, Ni(2) is bonded to one O(1), one O(3), one O(4), one O(5), and two equivalent O(6) atoms to form NiO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with three equivalent Na(3)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Ni(3)O6 octahedra, and edges with three equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-18°. In the third Ni site, Ni(3) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form NiO6 octahedra that share  a cornercorner with one Na(1)O6 octahedra,  a cornercorner with one Na(3)O6 octahedra, corners with two equivalent Na(2)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, and edges with two equivalent Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-17°. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), two equivalent Na(3), one Ni(1), one Ni(2), and one Ni(3) atom to form ONa3Ni3 octahedra that share  a cornercorner with one O(4)Na3Ni3 octahedra, corners with two equivalent O(5)Na3Ni3 octahedra,  a cornercorner with one O(3)Na2Ni3 square pyramid, corners with two equivalent O(6)Na2Ni3 square pyramids,  an edgeedge with one O(1)Na3Ni3 octahedra, edges with two equivalent O(5)Na3Ni3 octahedra, edges with three equivalent O(4)Na3Ni3 octahedra, edges with two equivalent O(2)Na2Ni3 square pyramids, edges with two equivalent O(3)Na2Ni3 square pyramids, and edges with two equivalent O(6)Na2Ni3 square pyramids. The corner-sharing octahedral tilt angles range from 1-7°. In the second O site, O(2) is bonded to one Na(1), one Na(2), one Ni(1), and two equivalent Ni(3) atoms to form ONa2Ni3 square pyramids that share  a cornercorner with one O(4)Na3Ni3 octahedra,  a cornercorner with one O(5)Na3Ni3 octahedra,  a cornercorner with one O(2)Na2Ni3 square pyramid, corners with two equivalent O(6)Na2Ni3 square pyramids, corners with four equivalent O(3)Na2Ni3 square pyramids, edges with two equivalent O(1)Na3Ni3 octahedra, edges with two equivalent O(4)Na3Ni3 octahedra, edges with two equivalent O(5)Na3Ni3 octahedra,  an edgeedge with one O(2)Na2Ni3 square pyramid, and  an edgeedge with one O(3)Na2Ni3 square pyramid. The corner-sharing octahedral tilt angles range from 3-8°. In the third O site, O(3) is bonded to one Na(2), one Na(3), one Ni(2), and two equivalent Ni(3) atoms to form ONa2Ni3 square pyramids that share  a cornercorner with one O(1)Na3Ni3 octahedra,  a cornercorner with one O(3)Na2Ni3 square pyramid, corners with three equivalent O(6)Na2Ni3 square pyramids, corners with four equivalent O(2)Na2Ni3 square pyramids, edges with two equivalent O(1)Na3Ni3 octahedra, edges with two equivalent O(4)Na3Ni3 octahedra, edges with two equivalent O(5)Na3Ni3 octahedra,  an edgeedge with one O(2)Na2Ni3 square pyramid, and  an edgeedge with one O(3)Na2Ni3 square pyramid. The corner-sharing octahedral tilt angles are 7°. In the fourth O site, O(4) is bonded to one Na(3), two equivalent Na(1), one Ni(1), one Ni(2), and one Ni(3) atom to form ONa3Ni3 octahedra that share  a cornercorner with one O(1)Na3Ni3 octahedra, corners with two equivalent O(5)Na3Ni3 octahedra,  a cornercorner with one O(2)Na2Ni3 square pyramid, corners with two equivalent O(6)Na2Ni3 square pyramids,  an edgeedge with one O(4)Na3Ni3 octahedra, edges with two equivalent O(5)Na3Ni3 octahedra, edges with three equivalent O(1)Na3Ni3 octahedra, edges with two equivalent O(2)Na2Ni3 square pyramids, edges with two equivalent O(3)Na2Ni3 square pyramids, and edges with two equivalent O(6)Na2Ni3 square pyramids. The corner-sharing octahedral tilt angles are 1°. In the fifth O site, O(5) is bonded to one Na(1), one Na(2), one Na(3), one Ni(2), and two equivalent Ni(1) atoms to form ONa3Ni3 octahedra that share  a cornercorner with one O(5)Na3Ni3 octahedra, corners with two equivalent O(1)Na3Ni3 octahedra, corners with two equivalent O(4)Na3Ni3 octahedra,  a cornercorner with one O(2)Na2Ni3 square pyramid,  an edgeedge with one O(5)Na3Ni3 octahedra, edges with two equivalent O(1)Na3Ni3 octahedra, edges with two equivalent O(4)Na3Ni3 octahedra, edges with two equivalent O(2)Na2Ni3 square pyramids, edges with two equivalent O(3)Na2Ni3 square pyramids, and edges with three equivalent O(6)Na2Ni3 square pyramids. The corner-sharing octahedral tilt angles range from 0-7°. In the sixth O site, O(6) is bonded to one Na(1), one Na(3), one Ni(1), and two equivalent Ni(2) atoms to form ONa2Ni3 square pyramids that share corners with two equivalent O(1)Na3Ni3 octahedra, corners with two equivalent O(4)Na3Ni3 octahedra, corners with two equivalent O(2)Na2Ni3 square pyramids, corners with three equivalent O(3)Na2Ni3 square pyramids, edges with two equivalent O(1)Na3Ni3 octahedra, edges with two equivalent O(4)Na3Ni3 octahedra, edges with three equivalent O(5)Na3Ni3 octahedra, and  an edgeedge with one O(6)Na2Ni3 square pyramid. The corner-sharing octahedral tilt angles range from 1-5°.
Na5(NiO2)6 crystallizes in the triclinic P-1 space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1), one O(2), one O(5), one O(6), and two equivalent O(4) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Ni(3)O6 octahedra, corners with two equivalent Ni(2)O6 octahedra, corners with three equivalent Ni(1)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, edges with two equivalent Ni(3)O6 octahedra, and edges with three equivalent Na(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-17°. The Na(1)-O(1) bond length is 2.31 Å. The Na(1)-O(2) bond length is 2.31 Å. The Na(1)-O(5) bond length is 2.33 Å. The Na(1)-O(6) bond length is 2.30 Å. There is one shorter (2.36 Å) and one longer (2.37 Å) Na(1)-O(4) bond length. In the second Na site, Na(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms to form distorted NaO6 octahedra that share corners with two equivalent Ni(1)O6 octahedra, corners with four equivalent Ni(3)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, and edges with two equivalent Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 12-17°. Both Na(2)-O(2) bond lengths are 2.31 Å. Both Na(2)-O(3) bond lengths are 2.43 Å. Both Na(2)-O(5) bond lengths are 2.31 Å. In the third Na site, Na(3) is bonded to one O(3), one O(4), one O(5), one O(6), and two equivalent O(1) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Ni(3)O6 octahedra, corners with two equivalent Ni(1)O6 octahedra, corners with three equivalent Ni(2)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Na(3)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, edges with two equivalent Ni(3)O6 octahedra, and edges with three equivalent Na(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-18°. The Na(3)-O(3) bond length is 2.27 Å. The Na(3)-O(4) bond length is 2.41 Å. The Na(3)-O(5) bond length is 2.32 Å. The Na(3)-O(6) bond length is 2.25 Å. There is one shorter (2.32 Å) and one longer (2.39 Å) Na(3)-O(1) bond length. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(2), one O(4), one O(6), and two equivalent O(5) atoms to form NiO6 octahedra that share  a cornercorner with one Na(2)O6 octahedra, corners with two equivalent Na(3)O6 octahedra, corners with three equivalent Na(1)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Ni(1)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Ni(3)O6 octahedra, and edges with three equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-17°. The Ni(1)-O(1) bond length is 2.13 Å. The Ni(1)-O(2) bond length is 1.89 Å. The Ni(1)-O(4) bond length is 1.90 Å. The Ni(1)-O(6) bond length is 2.08 Å. There is one shorter (1.89 Å) and one longer (1.91 Å) Ni(1)-O(5) bond length. In the second Ni site, Ni(2) is bonded to one O(1), one O(3), one O(4), one O(5), and two equivalent O(6) atoms to form NiO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with three equivalent Na(3)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Ni(3)O6 octahedra, and edges with three equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-18°. The Ni(2)-O(1) bond length is 1.91 Å. The Ni(2)-O(3) bond length is 1.89 Å. The Ni(2)-O(4) bond length is 2.13 Å. The Ni(2)-O(5) bond length is 2.11 Å. Both Ni(2)-O(6) bond lengths are 1.88 Å. In the third Ni site, Ni(3) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form NiO6 octahedra that share  a cornercorner with one Na(1)O6 octahedra,  a cornercorner with one Na(3)O6 octahedra, corners with two equivalent Na(2)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, and edges with two equivalent Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-17°. The Ni(3)-O(1) bond length is 1.89 Å. The Ni(3)-O(4) bond length is 1.89 Å. There is one shorter (1.92 Å) and one longer (1.98 Å) Ni(3)-O(2) bond length. There is one shorter (1.91 Å) and one longer (2.00 Å) Ni(3)-O(3) bond length. There are six inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), two equivalent Na(3), one Ni(1), one Ni(2), and one Ni(3) atom to form ONa3Ni3 octahedra that share  a cornercorner with one O(4)Na3Ni3 octahedra, corners with two equivalent O(5)Na3Ni3 octahedra,  a cornercorner with one O(3)Na2Ni3 square pyramid, corners with two equivalent O(6)Na2Ni3 square pyramids,  an edgeedge with one O(1)Na3Ni3 octahedra, edges with two equivalent O(5)Na3Ni3 octahedra, edges with three equivalent O(4)Na3Ni3 octahedra, edges with two equivalent O(2)Na2Ni3 square pyramids, edges with two equivalent O(3)Na2Ni3 square pyramids, and edges with two equivalent O(6)Na2Ni3 square pyramids. The corner-sharing octahedral tilt angles range from 1-7°. In the second O site, O(2) is bonded to one Na(1), one Na(2), one Ni(1), and two equivalent Ni(3) atoms to form ONa2Ni3 square pyramids that share  a cornercorner with one O(4)Na3Ni3 octahedra,  a cornercorner with one O(5)Na3Ni3 octahedra,  a cornercorner with one O(2)Na2Ni3 square pyramid, corners with two equivalent O(6)Na2Ni3 square pyramids, corners with four equivalent O(3)Na2Ni3 square pyramids, edges with two equivalent O(1)Na3Ni3 octahedra, edges with two equivalent O(4)Na3Ni3 octahedra, edges with two equivalent O(5)Na3Ni3 octahedra,  an edgeedge with one O(2)Na2Ni3 square pyramid, and  an edgeedge with one O(3)Na2Ni3 square pyramid. The corner-sharing octahedral tilt angles range from 3-8°. In the third O site, O(3) is bonded to one Na(2), one Na(3), one Ni(2), and two equivalent Ni(3) atoms to form ONa2Ni3 square pyramids that share  a cornercorner with one O(1)Na3Ni3 octahedra,  a cornercorner with one O(3)Na2Ni3 square pyramid, corners with three equivalent O(6)Na2Ni3 square pyramids, corners with four equivalent O(2)Na2Ni3 square pyramids, edges with two equivalent O(1)Na3Ni3 octahedra, edges with two equivalent O(4)Na3Ni3 octahedra, edges with two equivalent O(5)Na3Ni3 octahedra,  an edgeedge with one O(2)Na2Ni3 square pyramid, and  an edgeedge with one O(3)Na2Ni3 square pyramid. The corner-sharing octahedral tilt angles are 7°. In the fourth O site, O(4) is bonded to one Na(3), two equivalent Na(1), one Ni(1), one Ni(2), and one Ni(3) atom to form ONa3Ni3 octahedra that share  a cornercorner with one O(1)Na3Ni3 octahedra, corners with two equivalent O(5)Na3Ni3 octahedra,  a cornercorner with one O(2)Na2Ni3 square pyramid, corners with two equivalent O(6)Na2Ni3 square pyramids,  an edgeedge with one O(4)Na3Ni3 octahedra, edges with two equivalent O(5)Na3Ni3 octahedra, edges with three equivalent O(1)Na3Ni3 octahedra, edges with two equivalent O(2)Na2Ni3 square pyramids, edges with two equivalent O(3)Na2Ni3 square pyramids, and edges with two equivalent O(6)Na2Ni3 square pyramids. The corner-sharing octahedral tilt angles are 1°. In the fifth O site, O(5) is bonded to one Na(1), one Na(2), one Na(3), one Ni(2), and two equivalent Ni(1) atoms to form ONa3Ni3 octahedra that share  a cornercorner with one O(5)Na3Ni3 octahedra, corners with two equivalent O(1)Na3Ni3 octahedra, corners with two equivalent O(4)Na3Ni3 octahedra,  a cornercorner with one O(2)Na2Ni3 square pyramid,  an edgeedge with one O(5)Na3Ni3 octahedra, edges with two equivalent O(1)Na3Ni3 octahedra, edges with two equivalent O(4)Na3Ni3 octahedra, edges with two equivalent O(2)Na2Ni3 square pyramids, edges with two equivalent O(3)Na2Ni3 square pyramids, and edges with three equivalent O(6)Na2Ni3 square pyramids. The corner-sharing octahedral tilt angles range from 0-7°. In the sixth O site, O(6) is bonded to one Na(1), one Na(3), one Ni(1), and two equivalent Ni(2) atoms to form ONa2Ni3 square pyramids that share corners with two equivalent O(1)Na3Ni3 octahedra, corners with two equivalent O(4)Na3Ni3 octahedra, corners with two equivalent O(2)Na2Ni3 square pyramids, corners with three equivalent O(3)Na2Ni3 square pyramids, edges with two equivalent O(1)Na3Ni3 octahedra, edges with two equivalent O(4)Na3Ni3 octahedra, edges with three equivalent O(5)Na3Ni3 octahedra, and  an edgeedge with one O(6)Na2Ni3 square pyramid. The corner-sharing octahedral tilt angles range from 1-5°.