Na2Ni2O5 crystallizes in the triclinic P1 space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(10), one O(2), one O(4), one O(5), one O(7), and one O(9) atom to form NaO6 octahedra that share  an edgeedge with one Ni(1)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra, edges with two equivalent Ni(3)O6 octahedra, and edges with two equivalent Ni(4)O6 octahedra. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(10), one O(3), one O(4), one O(5), one O(6), and one O(9) atom. In the third Na site, Na(3) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(2), one O(5), one O(7), and one O(8) atom. In the fourth Na site, Na(4) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(4), one O(6), one O(8), and one O(9) atom. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(2), one O(3), one O(5), one O(6), and one O(8) atom to form NiO6 octahedra that share  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, and edges with two equivalent Ni(3)O6 octahedra. In the second Ni site, Ni(2) is bonded to one O(1), one O(10), one O(3), one O(4), one O(6), and one O(8) atom to form NiO6 octahedra that share  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Ni(3)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, and edges with two equivalent Ni(4)O6 octahedra. In the third Ni site, Ni(3) is bonded to one O(1), one O(2), one O(5), one O(6), one O(7), and one O(9) atom to form NiO6 octahedra that share  an edgeedge with one Ni(2)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. In the fourth Ni site, Ni(4) is bonded to one O(10), one O(3), one O(4), one O(7), one O(8), and one O(9) atom to form NiO6 octahedra that share  an edgeedge with one Ni(1)O6 octahedra,  an edgeedge with one Ni(3)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, and edges with two equivalent Ni(2)O6 octahedra. There are ten inequivalent O sites. In the first O site, O(1) is bonded to one Na(3), one Ni(1), one Ni(2), and one Ni(3) atom to form distorted ONaNi3 trigonal pyramids that share  a cornercorner with one O(6)Na2Ni3 square pyramid,  a cornercorner with one O(8)Na2Ni3 square pyramid,  a cornercorner with one O(2)Na3Ni2 square pyramid,  a cornercorner with one O(4)Na3Ni2 square pyramid,  a cornercorner with one O(5)Na3Ni2 square pyramid,  a cornercorner with one O(9)Na3Ni2 square pyramid, corners with two equivalent O(10)Na3Ni2 square pyramids,  an edgeedge with one O(3)Na2Ni3 square pyramid,  an edgeedge with one O(6)Na2Ni3 square pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid, and  an edgeedge with one O(5)Na3Ni2 square pyramid. In the second O site, O(2) is bonded to one Na(1), one Na(3), one Na(4), one Ni(1), and one Ni(3) atom to form distorted ONa3Ni2 square pyramids that share  a cornercorner with one O(6)Na2Ni3 square pyramid,  a cornercorner with one O(8)Na2Ni3 square pyramid,  a cornercorner with one O(9)Na3Ni2 square pyramid, corners with two equivalent O(4)Na3Ni2 square pyramids, corners with two equivalent O(5)Na3Ni2 square pyramids,  a cornercorner with one O(1)NaNi3 trigonal pyramid,  an edgeedge with one O(3)Na2Ni3 square pyramid,  an edgeedge with one O(6)Na2Ni3 square pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(5)Na3Ni2 square pyramid,  an edgeedge with one O(9)Na3Ni2 square pyramid, and  an edgeedge with one O(1)NaNi3 trigonal pyramid. In the third O site, O(3) is bonded to one Na(2), one Na(4), one Ni(1), one Ni(2), and one Ni(4) atom to form distorted ONa2Ni3 square pyramids that share  a cornercorner with one O(10)Na3Ni2 square pyramid, corners with two equivalent O(8)Na2Ni3 square pyramids, corners with two equivalent O(5)Na3Ni2 square pyramids, corners with three equivalent O(9)Na3Ni2 square pyramids,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid, edges with two equivalent O(6)Na2Ni3 square pyramids, edges with two equivalent O(4)Na3Ni2 square pyramids, and  an edgeedge with one O(1)NaNi3 trigonal pyramid. In the fourth O site, O(4) is bonded to one Na(1), one Na(2), one Na(4), one Ni(2), and one Ni(4) atom to form ONa3Ni2 square pyramids that share  a cornercorner with one O(8)Na2Ni3 square pyramid, corners with two equivalent O(10)Na3Ni2 square pyramids, corners with two equivalent O(2)Na3Ni2 square pyramids, corners with three equivalent O(6)Na2Ni3 square pyramids,  a cornercorner with one O(1)NaNi3 trigonal pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(5)Na3Ni2 square pyramid, edges with two equivalent O(3)Na2Ni3 square pyramids, and edges with two equivalent O(9)Na3Ni2 square pyramids. In the fifth O site, O(5) is bonded to one Na(1), one Na(2), one Na(3), one Ni(1), and one Ni(3) atom to form ONa3Ni2 square pyramids that share  a cornercorner with one O(6)Na2Ni3 square pyramid,  a cornercorner with one O(10)Na3Ni2 square pyramid,  a cornercorner with one O(9)Na3Ni2 square pyramid, corners with two equivalent O(3)Na2Ni3 square pyramids, corners with two equivalent O(2)Na3Ni2 square pyramids,  a cornercorner with one O(1)NaNi3 trigonal pyramid,  an edgeedge with one O(6)Na2Ni3 square pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid,  an edgeedge with one O(4)Na3Ni2 square pyramid,  an edgeedge with one O(9)Na3Ni2 square pyramid, and  an edgeedge with one O(1)NaNi3 trigonal pyramid. In the sixth O site, O(6) is bonded to one Na(2), one Na(4), one Ni(1), one Ni(2), and one Ni(3) atom to form ONa2Ni3 square pyramids that share  a cornercorner with one O(8)Na2Ni3 square pyramid,  a cornercorner with one O(2)Na3Ni2 square pyramid,  a cornercorner with one O(5)Na3Ni2 square pyramid,  a cornercorner with one O(9)Na3Ni2 square pyramid, corners with three equivalent O(4)Na3Ni2 square pyramids,  a cornercorner with one O(1)NaNi3 trigonal pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid,  an edgeedge with one O(5)Na3Ni2 square pyramid,  an edgeedge with one O(9)Na3Ni2 square pyramid, edges with two equivalent O(3)Na2Ni3 square pyramids, and  an edgeedge with one O(1)NaNi3 trigonal pyramid. In the seventh O site, O(7) is bonded in a rectangular see-saw-like geometry to one Na(1), one Na(3), one Ni(3), and one Ni(4) atom. In the eighth O site, O(8) is bonded to one Na(3), one Na(4), one Ni(1), one Ni(2), and one Ni(4) atom to form ONa2Ni3 square pyramids that share  a cornercorner with one O(6)Na2Ni3 square pyramid,  a cornercorner with one O(10)Na3Ni2 square pyramid,  a cornercorner with one O(2)Na3Ni2 square pyramid,  a cornercorner with one O(4)Na3Ni2 square pyramid, corners with two equivalent O(3)Na2Ni3 square pyramids,  a cornercorner with one O(1)NaNi3 trigonal pyramid,  an edgeedge with one O(3)Na2Ni3 square pyramid,  an edgeedge with one O(6)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid,  an edgeedge with one O(4)Na3Ni2 square pyramid,  an edgeedge with one O(5)Na3Ni2 square pyramid,  an edgeedge with one O(9)Na3Ni2 square pyramid, and  an edgeedge with one O(1)NaNi3 trigonal pyramid. In the ninth O site, O(9) is bonded to one Na(1), one Na(2), one Na(4), one Ni(3), and one Ni(4) atom to form ONa3Ni2 square pyramids that share  a cornercorner with one O(6)Na2Ni3 square pyramid,  a cornercorner with one O(10)Na3Ni2 square pyramid,  a cornercorner with one O(2)Na3Ni2 square pyramid,  a cornercorner with one O(5)Na3Ni2 square pyramid, corners with three equivalent O(3)Na2Ni3 square pyramids,  a cornercorner with one O(1)NaNi3 trigonal pyramid,  an edgeedge with one O(6)Na2Ni3 square pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid,  an edgeedge with one O(5)Na3Ni2 square pyramid, and edges with two equivalent O(4)Na3Ni2 square pyramids. In the tenth O site, O(10) is bonded to one Na(1), one Na(2), one Na(3), one Ni(2), and one Ni(4) atom to form distorted ONa3Ni2 square pyramids that share  a cornercorner with one O(3)Na2Ni3 square pyramid,  a cornercorner with one O(8)Na2Ni3 square pyramid,  a cornercorner with one O(5)Na3Ni2 square pyramid,  a cornercorner with one O(9)Na3Ni2 square pyramid, corners with two equivalent O(4)Na3Ni2 square pyramids, corners with two equivalent O(1)NaNi3 trigonal pyramids,  an edgeedge with one O(3)Na2Ni3 square pyramid,  an edgeedge with one O(6)Na2Ni3 square pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid,  an edgeedge with one O(4)Na3Ni2 square pyramid,  an edgeedge with one O(5)Na3Ni2 square pyramid, and  an edgeedge with one O(9)Na3Ni2 square pyramid.
Na2Ni2O5 crystallizes in the triclinic P1 space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(10), one O(2), one O(4), one O(5), one O(7), and one O(9) atom to form NaO6 octahedra that share  an edgeedge with one Ni(1)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra, edges with two equivalent Ni(3)O6 octahedra, and edges with two equivalent Ni(4)O6 octahedra. The Na(1)-O(10) bond length is 2.17 Å. The Na(1)-O(2) bond length is 2.15 Å. The Na(1)-O(4) bond length is 2.20 Å. The Na(1)-O(5) bond length is 2.20 Å. The Na(1)-O(7) bond length is 2.17 Å. The Na(1)-O(9) bond length is 2.23 Å. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(10), one O(3), one O(4), one O(5), one O(6), and one O(9) atom. The Na(2)-O(10) bond length is 2.30 Å. The Na(2)-O(3) bond length is 2.38 Å. The Na(2)-O(4) bond length is 2.40 Å. The Na(2)-O(5) bond length is 2.36 Å. The Na(2)-O(6) bond length is 2.49 Å. The Na(2)-O(9) bond length is 2.30 Å. In the third Na site, Na(3) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(2), one O(5), one O(7), and one O(8) atom. The Na(3)-O(1) bond length is 2.35 Å. The Na(3)-O(10) bond length is 2.40 Å. The Na(3)-O(2) bond length is 2.40 Å. The Na(3)-O(5) bond length is 2.35 Å. The Na(3)-O(7) bond length is 2.31 Å. The Na(3)-O(8) bond length is 2.45 Å. In the fourth Na site, Na(4) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(4), one O(6), one O(8), and one O(9) atom. The Na(4)-O(2) bond length is 2.28 Å. The Na(4)-O(3) bond length is 2.46 Å. The Na(4)-O(4) bond length is 2.48 Å. The Na(4)-O(6) bond length is 2.44 Å. The Na(4)-O(8) bond length is 2.35 Å. The Na(4)-O(9) bond length is 2.30 Å. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(2), one O(3), one O(5), one O(6), and one O(8) atom to form NiO6 octahedra that share  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, and edges with two equivalent Ni(3)O6 octahedra. The Ni(1)-O(1) bond length is 1.89 Å. The Ni(1)-O(2) bond length is 1.87 Å. The Ni(1)-O(3) bond length is 1.93 Å. The Ni(1)-O(5) bond length is 1.87 Å. The Ni(1)-O(6) bond length is 1.92 Å. The Ni(1)-O(8) bond length is 1.93 Å. In the second Ni site, Ni(2) is bonded to one O(1), one O(10), one O(3), one O(4), one O(6), and one O(8) atom to form NiO6 octahedra that share  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Ni(3)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, and edges with two equivalent Ni(4)O6 octahedra. The Ni(2)-O(1) bond length is 1.92 Å. The Ni(2)-O(10) bond length is 1.87 Å. The Ni(2)-O(3) bond length is 1.91 Å. The Ni(2)-O(4) bond length is 1.87 Å. The Ni(2)-O(6) bond length is 1.93 Å. The Ni(2)-O(8) bond length is 1.90 Å. In the third Ni site, Ni(3) is bonded to one O(1), one O(2), one O(5), one O(6), one O(7), and one O(9) atom to form NiO6 octahedra that share  an edgeedge with one Ni(2)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The Ni(3)-O(1) bond length is 1.93 Å. The Ni(3)-O(2) bond length is 1.89 Å. The Ni(3)-O(5) bond length is 1.89 Å. The Ni(3)-O(6) bond length is 1.93 Å. The Ni(3)-O(7) bond length is 1.89 Å. The Ni(3)-O(9) bond length is 1.90 Å. In the fourth Ni site, Ni(4) is bonded to one O(10), one O(3), one O(4), one O(7), one O(8), and one O(9) atom to form NiO6 octahedra that share  an edgeedge with one Ni(1)O6 octahedra,  an edgeedge with one Ni(3)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, and edges with two equivalent Ni(2)O6 octahedra. The Ni(4)-O(10) bond length is 1.89 Å. The Ni(4)-O(3) bond length is 1.94 Å. The Ni(4)-O(4) bond length is 1.91 Å. The Ni(4)-O(7) bond length is 1.87 Å. The Ni(4)-O(8) bond length is 1.95 Å. The Ni(4)-O(9) bond length is 1.88 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded to one Na(3), one Ni(1), one Ni(2), and one Ni(3) atom to form distorted ONaNi3 trigonal pyramids that share  a cornercorner with one O(6)Na2Ni3 square pyramid,  a cornercorner with one O(8)Na2Ni3 square pyramid,  a cornercorner with one O(2)Na3Ni2 square pyramid,  a cornercorner with one O(4)Na3Ni2 square pyramid,  a cornercorner with one O(5)Na3Ni2 square pyramid,  a cornercorner with one O(9)Na3Ni2 square pyramid, corners with two equivalent O(10)Na3Ni2 square pyramids,  an edgeedge with one O(3)Na2Ni3 square pyramid,  an edgeedge with one O(6)Na2Ni3 square pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid, and  an edgeedge with one O(5)Na3Ni2 square pyramid. In the second O site, O(2) is bonded to one Na(1), one Na(3), one Na(4), one Ni(1), and one Ni(3) atom to form distorted ONa3Ni2 square pyramids that share  a cornercorner with one O(6)Na2Ni3 square pyramid,  a cornercorner with one O(8)Na2Ni3 square pyramid,  a cornercorner with one O(9)Na3Ni2 square pyramid, corners with two equivalent O(4)Na3Ni2 square pyramids, corners with two equivalent O(5)Na3Ni2 square pyramids,  a cornercorner with one O(1)NaNi3 trigonal pyramid,  an edgeedge with one O(3)Na2Ni3 square pyramid,  an edgeedge with one O(6)Na2Ni3 square pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(5)Na3Ni2 square pyramid,  an edgeedge with one O(9)Na3Ni2 square pyramid, and  an edgeedge with one O(1)NaNi3 trigonal pyramid. In the third O site, O(3) is bonded to one Na(2), one Na(4), one Ni(1), one Ni(2), and one Ni(4) atom to form distorted ONa2Ni3 square pyramids that share  a cornercorner with one O(10)Na3Ni2 square pyramid, corners with two equivalent O(8)Na2Ni3 square pyramids, corners with two equivalent O(5)Na3Ni2 square pyramids, corners with three equivalent O(9)Na3Ni2 square pyramids,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid, edges with two equivalent O(6)Na2Ni3 square pyramids, edges with two equivalent O(4)Na3Ni2 square pyramids, and  an edgeedge with one O(1)NaNi3 trigonal pyramid. In the fourth O site, O(4) is bonded to one Na(1), one Na(2), one Na(4), one Ni(2), and one Ni(4) atom to form ONa3Ni2 square pyramids that share  a cornercorner with one O(8)Na2Ni3 square pyramid, corners with two equivalent O(10)Na3Ni2 square pyramids, corners with two equivalent O(2)Na3Ni2 square pyramids, corners with three equivalent O(6)Na2Ni3 square pyramids,  a cornercorner with one O(1)NaNi3 trigonal pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(5)Na3Ni2 square pyramid, edges with two equivalent O(3)Na2Ni3 square pyramids, and edges with two equivalent O(9)Na3Ni2 square pyramids. In the fifth O site, O(5) is bonded to one Na(1), one Na(2), one Na(3), one Ni(1), and one Ni(3) atom to form ONa3Ni2 square pyramids that share  a cornercorner with one O(6)Na2Ni3 square pyramid,  a cornercorner with one O(10)Na3Ni2 square pyramid,  a cornercorner with one O(9)Na3Ni2 square pyramid, corners with two equivalent O(3)Na2Ni3 square pyramids, corners with two equivalent O(2)Na3Ni2 square pyramids,  a cornercorner with one O(1)NaNi3 trigonal pyramid,  an edgeedge with one O(6)Na2Ni3 square pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid,  an edgeedge with one O(4)Na3Ni2 square pyramid,  an edgeedge with one O(9)Na3Ni2 square pyramid, and  an edgeedge with one O(1)NaNi3 trigonal pyramid. In the sixth O site, O(6) is bonded to one Na(2), one Na(4), one Ni(1), one Ni(2), and one Ni(3) atom to form ONa2Ni3 square pyramids that share  a cornercorner with one O(8)Na2Ni3 square pyramid,  a cornercorner with one O(2)Na3Ni2 square pyramid,  a cornercorner with one O(5)Na3Ni2 square pyramid,  a cornercorner with one O(9)Na3Ni2 square pyramid, corners with three equivalent O(4)Na3Ni2 square pyramids,  a cornercorner with one O(1)NaNi3 trigonal pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid,  an edgeedge with one O(5)Na3Ni2 square pyramid,  an edgeedge with one O(9)Na3Ni2 square pyramid, edges with two equivalent O(3)Na2Ni3 square pyramids, and  an edgeedge with one O(1)NaNi3 trigonal pyramid. In the seventh O site, O(7) is bonded in a rectangular see-saw-like geometry to one Na(1), one Na(3), one Ni(3), and one Ni(4) atom. In the eighth O site, O(8) is bonded to one Na(3), one Na(4), one Ni(1), one Ni(2), and one Ni(4) atom to form ONa2Ni3 square pyramids that share  a cornercorner with one O(6)Na2Ni3 square pyramid,  a cornercorner with one O(10)Na3Ni2 square pyramid,  a cornercorner with one O(2)Na3Ni2 square pyramid,  a cornercorner with one O(4)Na3Ni2 square pyramid, corners with two equivalent O(3)Na2Ni3 square pyramids,  a cornercorner with one O(1)NaNi3 trigonal pyramid,  an edgeedge with one O(3)Na2Ni3 square pyramid,  an edgeedge with one O(6)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid,  an edgeedge with one O(4)Na3Ni2 square pyramid,  an edgeedge with one O(5)Na3Ni2 square pyramid,  an edgeedge with one O(9)Na3Ni2 square pyramid, and  an edgeedge with one O(1)NaNi3 trigonal pyramid. In the ninth O site, O(9) is bonded to one Na(1), one Na(2), one Na(4), one Ni(3), and one Ni(4) atom to form ONa3Ni2 square pyramids that share  a cornercorner with one O(6)Na2Ni3 square pyramid,  a cornercorner with one O(10)Na3Ni2 square pyramid,  a cornercorner with one O(2)Na3Ni2 square pyramid,  a cornercorner with one O(5)Na3Ni2 square pyramid, corners with three equivalent O(3)Na2Ni3 square pyramids,  a cornercorner with one O(1)NaNi3 trigonal pyramid,  an edgeedge with one O(6)Na2Ni3 square pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid,  an edgeedge with one O(5)Na3Ni2 square pyramid, and edges with two equivalent O(4)Na3Ni2 square pyramids. In the tenth O site, O(10) is bonded to one Na(1), one Na(2), one Na(3), one Ni(2), and one Ni(4) atom to form distorted ONa3Ni2 square pyramids that share  a cornercorner with one O(3)Na2Ni3 square pyramid,  a cornercorner with one O(8)Na2Ni3 square pyramid,  a cornercorner with one O(5)Na3Ni2 square pyramid,  a cornercorner with one O(9)Na3Ni2 square pyramid, corners with two equivalent O(4)Na3Ni2 square pyramids, corners with two equivalent O(1)NaNi3 trigonal pyramids,  an edgeedge with one O(3)Na2Ni3 square pyramid,  an edgeedge with one O(6)Na2Ni3 square pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid,  an edgeedge with one O(4)Na3Ni2 square pyramid,  an edgeedge with one O(5)Na3Ni2 square pyramid, and  an edgeedge with one O(9)Na3Ni2 square pyramid.