Na6NiO4 is alpha Pu-derived structured and crystallizes in the triclinic P1 space group. There are twenty-four inequivalent Na sites. In the first Na site, Na(1) is bonded in a 4-coordinate geometry to one O(1), one O(11), one O(13), and one O(6) atom. In the second Na site, Na(2) is bonded to one O(12), one O(14), one O(2), and one O(5) atom to form distorted NaO4 trigonal pyramids that share corners with two equivalent Ni(2)O4 tetrahedra,  a cornercorner with one Na(5)O4 trigonal pyramid,  a cornercorner with one Na(6)O4 trigonal pyramid,  a cornercorner with one Na(9)O4 trigonal pyramid, corners with two equivalent Na(4)O4 trigonal pyramids, corners with two equivalent Na(8)O4 trigonal pyramids, and  an edgeedge with one Ni(3)O4 tetrahedra. In the third Na site, Na(3) is bonded to one O(1), one O(11), one O(15), and one O(8) atom to form distorted NaO4 trigonal pyramids that share corners with two equivalent Ni(4)O4 tetrahedra,  a cornercorner with one Na(11)O4 trigonal pyramid,  a cornercorner with one Na(12)O4 trigonal pyramid,  a cornercorner with one Na(5)O4 trigonal pyramid,  a cornercorner with one Na(6)O4 trigonal pyramid, corners with two equivalent Na(7)O4 trigonal pyramids, and  an edgeedge with one Ni(1)O4 tetrahedra. In the fourth Na site, Na(4) is bonded to one O(12), one O(16), one O(2), and one O(7) atom to form distorted NaO4 trigonal pyramids that share corners with two equivalent Ni(2)O4 tetrahedra,  a cornercorner with one Na(11)O4 trigonal pyramid,  a cornercorner with one Na(12)O4 trigonal pyramid,  a cornercorner with one Na(5)O4 trigonal pyramid,  a cornercorner with one Na(6)O4 trigonal pyramid, corners with two equivalent Na(2)O4 trigonal pyramids, corners with two equivalent Na(8)O4 trigonal pyramids, and  an edgeedge with one Ni(3)O4 tetrahedra. In the fifth Na site, Na(5) is bonded to one O(11), one O(3), one O(5), and one O(7) atom to form distorted NaO4 trigonal pyramids that share corners with two equivalent Ni(3)O4 tetrahedra,  a cornercorner with one Na(2)O4 trigonal pyramid,  a cornercorner with one Na(3)O4 trigonal pyramid,  a cornercorner with one Na(4)O4 trigonal pyramid, corners with two equivalent Na(11)O4 trigonal pyramids, corners with two equivalent Na(9)O4 trigonal pyramids, and  an edgeedge with one Ni(4)O4 tetrahedra. In the sixth Na site, Na(6) is bonded to one O(12), one O(4), one O(6), and one O(8) atom to form distorted NaO4 trigonal pyramids that share corners with two equivalent Ni(1)O4 tetrahedra,  a cornercorner with one Na(2)O4 trigonal pyramid,  a cornercorner with one Na(3)O4 trigonal pyramid,  a cornercorner with one Na(4)O4 trigonal pyramid, corners with two equivalent Na(12)O4 trigonal pyramids, and  an edgeedge with one Ni(2)O4 tetrahedra. In the seventh Na site, Na(7) is bonded to one O(1), one O(10), one O(13), and one O(15) atom to form distorted NaO4 trigonal pyramids that share corners with two equivalent Ni(4)O4 tetrahedra,  a cornercorner with one Na(11)O4 trigonal pyramid,  a cornercorner with one Na(12)O4 trigonal pyramid,  a cornercorner with one Na(9)O4 trigonal pyramid, corners with two equivalent Na(3)O4 trigonal pyramids, and  an edgeedge with one Ni(1)O4 tetrahedra. In the eighth Na site, Na(8) is bonded to one O(14), one O(16), one O(2), and one O(9) atom to form distorted NaO4 trigonal pyramids that share corners with two equivalent Ni(2)O4 tetrahedra,  a cornercorner with one Na(11)O4 trigonal pyramid,  a cornercorner with one Na(12)O4 trigonal pyramid,  a cornercorner with one Na(9)O4 trigonal pyramid, corners with two equivalent Na(2)O4 trigonal pyramids, corners with two equivalent Na(4)O4 trigonal pyramids, and  an edgeedge with one Ni(3)O4 tetrahedra. In the ninth Na site, Na(9) is bonded to one O(13), one O(3), one O(5), and one O(9) atom to form distorted NaO4 trigonal pyramids that share corners with two equivalent Ni(3)O4 tetrahedra,  a cornercorner with one Na(2)O4 trigonal pyramid,  a cornercorner with one Na(7)O4 trigonal pyramid,  a cornercorner with one Na(8)O4 trigonal pyramid, corners with two equivalent Na(11)O4 trigonal pyramids, corners with two equivalent Na(5)O4 trigonal pyramids, and  an edgeedge with one Ni(4)O4 tetrahedra. In the tenth Na site, Na(10) is bonded in a 4-coordinate geometry to one O(10), one O(14), one O(4), and one O(6) atom. In the eleventh Na site, Na(11) is bonded to one O(15), one O(3), one O(7), and one O(9) atom to form distorted NaO4 trigonal pyramids that share corners with two equivalent Ni(3)O4 tetrahedra,  a cornercorner with one Na(3)O4 trigonal pyramid,  a cornercorner with one Na(4)O4 trigonal pyramid,  a cornercorner with one Na(7)O4 trigonal pyramid,  a cornercorner with one Na(8)O4 trigonal pyramid, corners with two equivalent Na(5)O4 trigonal pyramids, corners with two equivalent Na(9)O4 trigonal pyramids, and  an edgeedge with one Ni(4)O4 tetrahedra. In the twelfth Na site, Na(12) is bonded to one O(10), one O(16), one O(4), and one O(8) atom to form distorted NaO4 trigonal pyramids that share corners with two equivalent Ni(1)O4 tetrahedra,  a cornercorner with one Na(3)O4 trigonal pyramid,  a cornercorner with one Na(4)O4 trigonal pyramid,  a cornercorner with one Na(7)O4 trigonal pyramid,  a cornercorner with one Na(8)O4 trigonal pyramid, corners with two equivalent Na(6)O4 trigonal pyramids, and  an edgeedge with one Ni(2)O4 tetrahedra. In the thirteenth Na site, Na(13) is bonded in a 3-coordinate geometry to one O(1), one O(13), one O(15), one O(5), and one O(7) atom. In the fourteenth Na site, Na(14) is bonded in a 3-coordinate geometry to one O(14), one O(16), one O(2), one O(6), and one O(8) atom. In the fifteenth Na site, Na(15) is bonded in a 3-coordinate geometry to one O(1), one O(11), one O(15), one O(5), and one O(9) atom. In the sixteenth Na site, Na(16) is bonded in a 5-coordinate geometry to one O(10), one O(12), one O(16), one O(2), and one O(6) atom. In the seventeenth Na site, Na(17) is bonded in a 3-coordinate geometry to one O(1), one O(11), one O(13), one O(7), and one O(9) atom. In the eighteenth Na site, Na(18) is bonded in a 3-coordinate geometry to one O(10), one O(12), one O(14), one O(2), and one O(8) atom. In the nineteenth Na site, Na(19) is bonded in a 3-coordinate geometry to one O(12), one O(14), one O(3), one O(7), and one O(9) atom. In the twentieth Na site, Na(20) is bonded in a 5-coordinate geometry to one O(10), one O(11), one O(13), one O(4), and one O(8) atom. In the twenty-first Na site, Na(21) is bonded in a 3-coordinate geometry to one O(12), one O(16), one O(3), one O(5), and one O(9) atom. In the twenty-second Na site, Na(22) is bonded in a 3-coordinate geometry to one O(10), one O(11), one O(15), one O(4), and one O(6) atom. In the twenty-third Na site, Na(23) is bonded in a 3-coordinate geometry to one O(14), one O(16), one O(3), one O(5), and one O(7) atom. In the twenty-fourth Na site, Na(24) is bonded in a 3-coordinate geometry to one O(13), one O(15), one O(4), one O(6), and one O(8) atom. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(10), one O(6), and one O(8) atom to form NiO4 tetrahedra that share corners with two equivalent Na(12)O4 trigonal pyramids, corners with two equivalent Na(6)O4 trigonal pyramids,  an edgeedge with one Na(3)O4 trigonal pyramid, and  an edgeedge with one Na(7)O4 trigonal pyramid. In the second Ni site, Ni(2) is bonded to one O(12), one O(14), one O(16), and one O(4) atom to form NiO4 tetrahedra that share corners with two equivalent Na(2)O4 trigonal pyramids, corners with two equivalent Na(4)O4 trigonal pyramids, corners with two equivalent Na(8)O4 trigonal pyramids,  an edgeedge with one Na(12)O4 trigonal pyramid, and  an edgeedge with one Na(6)O4 trigonal pyramid. In the third Ni site, Ni(3) is bonded to one O(2), one O(5), one O(7), and one O(9) atom to form NiO4 tetrahedra that share corners with two equivalent Na(11)O4 trigonal pyramids, corners with two equivalent Na(5)O4 trigonal pyramids, corners with two equivalent Na(9)O4 trigonal pyramids,  an edgeedge with one Na(2)O4 trigonal pyramid,  an edgeedge with one Na(4)O4 trigonal pyramid, and  an edgeedge with one Na(8)O4 trigonal pyramid. In the fourth Ni site, Ni(4) is bonded to one O(11), one O(13), one O(15), and one O(3) atom to form NiO4 tetrahedra that share corners with two equivalent Na(3)O4 trigonal pyramids, corners with two equivalent Na(7)O4 trigonal pyramids,  an edgeedge with one Na(11)O4 trigonal pyramid,  an edgeedge with one Na(5)O4 trigonal pyramid, and  an edgeedge with one Na(9)O4 trigonal pyramid. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded in a 7-coordinate geometry to one Na(1), one Na(13), one Na(15), one Na(17), one Na(3), one Na(7), and one Ni(1) atom. In the second O site, O(2) is bonded in a 7-coordinate geometry to one Na(14), one Na(16), one Na(18), one Na(2), one Na(4), one Na(8), and one Ni(3) atom. In the third O site, O(3) is bonded in a 7-coordinate geometry to one Na(11), one Na(19), one Na(21), one Na(23), one Na(5), one Na(9), and one Ni(4) atom. In the fourth O site, O(4) is bonded in a 7-coordinate geometry to one Na(10), one Na(12), one Na(20), one Na(22), one Na(24), one Na(6), and one Ni(2) atom. In the fifth O site, O(5) is bonded in a 8-coordinate geometry to one Na(13), one Na(15), one Na(2), one Na(21), one Na(23), one Na(5), one Na(9), and one Ni(3) atom. In the sixth O site, O(6) is bonded in a 8-coordinate geometry to one Na(1), one Na(10), one Na(14), one Na(16), one Na(22), one Na(24), one Na(6), and one Ni(1) atom. In the seventh O site, O(7) is bonded in a 8-coordinate geometry to one Na(11), one Na(13), one Na(17), one Na(19), one Na(23), one Na(4), one Na(5), and one Ni(3) atom. In the eighth O site, O(8) is bonded in a 8-coordinate geometry to one Na(12), one Na(14), one Na(18), one Na(20), one Na(24), one Na(3), one Na(6), and one Ni(1) atom. In the ninth O site, O(9) is bonded in a 8-coordinate geometry to one Na(11), one Na(15), one Na(17), one Na(19), one Na(21), one Na(8), one Na(9), and one Ni(3) atom. In the tenth O site, O(10) is bonded in a 8-coordinate geometry to one Na(10), one Na(12), one Na(16), one Na(18), one Na(20), one Na(22), one Na(7), and one Ni(1) atom. In the eleventh O site, O(11) is bonded in a 8-coordinate geometry to one Na(1), one Na(15), one Na(17), one Na(20), one Na(22), one Na(3), one Na(5), and one Ni(4) atom. In the twelfth O site, O(12) is bonded in a 8-coordinate geometry to one Na(16), one Na(18), one Na(19), one Na(2), one Na(21), one Na(4), one Na(6), and one Ni(2) atom. In the thirteenth O site, O(13) is bonded in a 8-coordinate geometry to one Na(1), one Na(13), one Na(17), one Na(20), one Na(24), one Na(7), one Na(9), and one Ni(4) atom. In the fourteenth O site, O(14) is bonded in a 8-coordinate geometry to one Na(10), one Na(14), one Na(18), one Na(19), one Na(2), one Na(23), one Na(8), and one Ni(2) atom. In the fifteenth O site, O(15) is bonded in a 8-coordinate geometry to one Na(11), one Na(13), one Na(15), one Na(22), one Na(24), one Na(3), one Na(7), and one Ni(4) atom. In the sixteenth O site, O(16) is bonded in a 8-coordinate geometry to one Na(12), one Na(14), one Na(16), one Na(21), one Na(23), one Na(4), one Na(8), and one Ni(2) atom.
Na6NiO4 is alpha Pu-derived structured and crystallizes in the triclinic P1 space group. There are twenty-four inequivalent Na sites. In the first Na site, Na(1) is bonded in a 4-coordinate geometry to one O(1), one O(11), one O(13), and one O(6) atom. The Na(1)-O(1) bond length is 2.58 Å. The Na(1)-O(11) bond length is 2.35 Å. The Na(1)-O(13) bond length is 2.35 Å. The Na(1)-O(6) bond length is 2.38 Å. In the second Na site, Na(2) is bonded to one O(12), one O(14), one O(2), and one O(5) atom to form distorted NaO4 trigonal pyramids that share corners with two equivalent Ni(2)O4 tetrahedra,  a cornercorner with one Na(5)O4 trigonal pyramid,  a cornercorner with one Na(6)O4 trigonal pyramid,  a cornercorner with one Na(9)O4 trigonal pyramid, corners with two equivalent Na(4)O4 trigonal pyramids, corners with two equivalent Na(8)O4 trigonal pyramids, and  an edgeedge with one Ni(3)O4 tetrahedra. The Na(2)-O(12) bond length is 2.35 Å. The Na(2)-O(14) bond length is 2.34 Å. The Na(2)-O(2) bond length is 2.59 Å. The Na(2)-O(5) bond length is 2.40 Å. In the third Na site, Na(3) is bonded to one O(1), one O(11), one O(15), and one O(8) atom to form distorted NaO4 trigonal pyramids that share corners with two equivalent Ni(4)O4 tetrahedra,  a cornercorner with one Na(11)O4 trigonal pyramid,  a cornercorner with one Na(12)O4 trigonal pyramid,  a cornercorner with one Na(5)O4 trigonal pyramid,  a cornercorner with one Na(6)O4 trigonal pyramid, corners with two equivalent Na(7)O4 trigonal pyramids, and  an edgeedge with one Ni(1)O4 tetrahedra. The Na(3)-O(1) bond length is 2.55 Å. The Na(3)-O(11) bond length is 2.37 Å. The Na(3)-O(15) bond length is 2.38 Å. The Na(3)-O(8) bond length is 2.38 Å. In the fourth Na site, Na(4) is bonded to one O(12), one O(16), one O(2), and one O(7) atom to form distorted NaO4 trigonal pyramids that share corners with two equivalent Ni(2)O4 tetrahedra,  a cornercorner with one Na(11)O4 trigonal pyramid,  a cornercorner with one Na(12)O4 trigonal pyramid,  a cornercorner with one Na(5)O4 trigonal pyramid,  a cornercorner with one Na(6)O4 trigonal pyramid, corners with two equivalent Na(2)O4 trigonal pyramids, corners with two equivalent Na(8)O4 trigonal pyramids, and  an edgeedge with one Ni(3)O4 tetrahedra. The Na(4)-O(12) bond length is 2.37 Å. The Na(4)-O(16) bond length is 2.37 Å. The Na(4)-O(2) bond length is 2.56 Å. The Na(4)-O(7) bond length is 2.39 Å. In the fifth Na site, Na(5) is bonded to one O(11), one O(3), one O(5), and one O(7) atom to form distorted NaO4 trigonal pyramids that share corners with two equivalent Ni(3)O4 tetrahedra,  a cornercorner with one Na(2)O4 trigonal pyramid,  a cornercorner with one Na(3)O4 trigonal pyramid,  a cornercorner with one Na(4)O4 trigonal pyramid, corners with two equivalent Na(11)O4 trigonal pyramids, corners with two equivalent Na(9)O4 trigonal pyramids, and  an edgeedge with one Ni(4)O4 tetrahedra. The Na(5)-O(11) bond length is 2.36 Å. The Na(5)-O(3) bond length is 2.55 Å. The Na(5)-O(5) bond length is 2.37 Å. The Na(5)-O(7) bond length is 2.37 Å. In the sixth Na site, Na(6) is bonded to one O(12), one O(4), one O(6), and one O(8) atom to form distorted NaO4 trigonal pyramids that share corners with two equivalent Ni(1)O4 tetrahedra,  a cornercorner with one Na(2)O4 trigonal pyramid,  a cornercorner with one Na(3)O4 trigonal pyramid,  a cornercorner with one Na(4)O4 trigonal pyramid, corners with two equivalent Na(12)O4 trigonal pyramids, and  an edgeedge with one Ni(2)O4 tetrahedra. The Na(6)-O(12) bond length is 2.38 Å. The Na(6)-O(4) bond length is 2.54 Å. The Na(6)-O(6) bond length is 2.36 Å. The Na(6)-O(8) bond length is 2.36 Å. In the seventh Na site, Na(7) is bonded to one O(1), one O(10), one O(13), and one O(15) atom to form distorted NaO4 trigonal pyramids that share corners with two equivalent Ni(4)O4 tetrahedra,  a cornercorner with one Na(11)O4 trigonal pyramid,  a cornercorner with one Na(12)O4 trigonal pyramid,  a cornercorner with one Na(9)O4 trigonal pyramid, corners with two equivalent Na(3)O4 trigonal pyramids, and  an edgeedge with one Ni(1)O4 tetrahedra. The Na(7)-O(1) bond length is 2.56 Å. The Na(7)-O(10) bond length is 2.37 Å. The Na(7)-O(13) bond length is 2.34 Å. The Na(7)-O(15) bond length is 2.34 Å. In the eighth Na site, Na(8) is bonded to one O(14), one O(16), one O(2), and one O(9) atom to form distorted NaO4 trigonal pyramids that share corners with two equivalent Ni(2)O4 tetrahedra,  a cornercorner with one Na(11)O4 trigonal pyramid,  a cornercorner with one Na(12)O4 trigonal pyramid,  a cornercorner with one Na(9)O4 trigonal pyramid, corners with two equivalent Na(2)O4 trigonal pyramids, corners with two equivalent Na(4)O4 trigonal pyramids, and  an edgeedge with one Ni(3)O4 tetrahedra. The Na(8)-O(14) bond length is 2.35 Å. The Na(8)-O(16) bond length is 2.36 Å. The Na(8)-O(2) bond length is 2.57 Å. The Na(8)-O(9) bond length is 2.39 Å. In the ninth Na site, Na(9) is bonded to one O(13), one O(3), one O(5), and one O(9) atom to form distorted NaO4 trigonal pyramids that share corners with two equivalent Ni(3)O4 tetrahedra,  a cornercorner with one Na(2)O4 trigonal pyramid,  a cornercorner with one Na(7)O4 trigonal pyramid,  a cornercorner with one Na(8)O4 trigonal pyramid, corners with two equivalent Na(11)O4 trigonal pyramids, corners with two equivalent Na(5)O4 trigonal pyramids, and  an edgeedge with one Ni(4)O4 tetrahedra. The Na(9)-O(13) bond length is 2.37 Å. The Na(9)-O(3) bond length is 2.57 Å. The Na(9)-O(5) bond length is 2.36 Å. The Na(9)-O(9) bond length is 2.36 Å. In the tenth Na site, Na(10) is bonded in a 4-coordinate geometry to one O(10), one O(14), one O(4), and one O(6) atom. The Na(10)-O(10) bond length is 2.32 Å. The Na(10)-O(14) bond length is 2.40 Å. The Na(10)-O(4) bond length is 2.62 Å. The Na(10)-O(6) bond length is 2.32 Å. In the eleventh Na site, Na(11) is bonded to one O(15), one O(3), one O(7), and one O(9) atom to form distorted NaO4 trigonal pyramids that share corners with two equivalent Ni(3)O4 tetrahedra,  a cornercorner with one Na(3)O4 trigonal pyramid,  a cornercorner with one Na(4)O4 trigonal pyramid,  a cornercorner with one Na(7)O4 trigonal pyramid,  a cornercorner with one Na(8)O4 trigonal pyramid, corners with two equivalent Na(5)O4 trigonal pyramids, corners with two equivalent Na(9)O4 trigonal pyramids, and  an edgeedge with one Ni(4)O4 tetrahedra. The Na(11)-O(15) bond length is 2.36 Å. The Na(11)-O(3) bond length is 2.56 Å. The Na(11)-O(7) bond length is 2.36 Å. The Na(11)-O(9) bond length is 2.36 Å. In the twelfth Na site, Na(12) is bonded to one O(10), one O(16), one O(4), and one O(8) atom to form distorted NaO4 trigonal pyramids that share corners with two equivalent Ni(1)O4 tetrahedra,  a cornercorner with one Na(3)O4 trigonal pyramid,  a cornercorner with one Na(4)O4 trigonal pyramid,  a cornercorner with one Na(7)O4 trigonal pyramid,  a cornercorner with one Na(8)O4 trigonal pyramid, corners with two equivalent Na(6)O4 trigonal pyramids, and  an edgeedge with one Ni(2)O4 tetrahedra. The Na(12)-O(10) bond length is 2.37 Å. The Na(12)-O(16) bond length is 2.38 Å. The Na(12)-O(4) bond length is 2.54 Å. The Na(12)-O(8) bond length is 2.37 Å. In the thirteenth Na site, Na(13) is bonded in a 3-coordinate geometry to one O(1), one O(13), one O(15), one O(5), and one O(7) atom. The Na(13)-O(1) bond length is 2.35 Å. The Na(13)-O(13) bond length is 2.77 Å. The Na(13)-O(15) bond length is 2.78 Å. The Na(13)-O(5) bond length is 2.42 Å. The Na(13)-O(7) bond length is 2.44 Å. In the fourteenth Na site, Na(14) is bonded in a 3-coordinate geometry to one O(14), one O(16), one O(2), one O(6), and one O(8) atom. The Na(14)-O(14) bond length is 2.76 Å. The Na(14)-O(16) bond length is 2.74 Å. The Na(14)-O(2) bond length is 2.33 Å. The Na(14)-O(6) bond length is 2.45 Å. The Na(14)-O(8) bond length is 2.46 Å. In the fifteenth Na site, Na(15) is bonded in a 3-coordinate geometry to one O(1), one O(11), one O(15), one O(5), and one O(9) atom. The Na(15)-O(1) bond length is 2.37 Å. The Na(15)-O(11) bond length is 2.72 Å. The Na(15)-O(15) bond length is 2.70 Å. The Na(15)-O(5) bond length is 2.44 Å. The Na(15)-O(9) bond length is 2.45 Å. In the sixteenth Na site, Na(16) is bonded in a 5-coordinate geometry to one O(10), one O(12), one O(16), one O(2), and one O(6) atom. The Na(16)-O(10) bond length is 2.51 Å. The Na(16)-O(12) bond length is 2.70 Å. The Na(16)-O(16) bond length is 2.70 Å. The Na(16)-O(2) bond length is 2.35 Å. The Na(16)-O(6) bond length is 2.50 Å. In the seventeenth Na site, Na(17) is bonded in a 3-coordinate geometry to one O(1), one O(11), one O(13), one O(7), and one O(9) atom. The Na(17)-O(1) bond length is 2.35 Å. The Na(17)-O(11) bond length is 2.76 Å. The Na(17)-O(13) bond length is 2.74 Å. The Na(17)-O(7) bond length is 2.44 Å. The Na(17)-O(9) bond length is 2.43 Å. In the eighteenth Na site, Na(18) is bonded in a 3-coordinate geometry to one O(10), one O(12), one O(14), one O(2), and one O(8) atom. The Na(18)-O(10) bond length is 2.44 Å. The Na(18)-O(12) bond length is 2.75 Å. The Na(18)-O(14) bond length is 2.76 Å. The Na(18)-O(2) bond length is 2.32 Å. The Na(18)-O(8) bond length is 2.44 Å. In the nineteenth Na site, Na(19) is bonded in a 3-coordinate geometry to one O(12), one O(14), one O(3), one O(7), and one O(9) atom. The Na(19)-O(12) bond length is 2.48 Å. The Na(19)-O(14) bond length is 2.46 Å. The Na(19)-O(3) bond length is 2.35 Å. The Na(19)-O(7) bond length is 2.73 Å. The Na(19)-O(9) bond length is 2.74 Å. In the twentieth Na site, Na(20) is bonded in a 5-coordinate geometry to one O(10), one O(11), one O(13), one O(4), and one O(8) atom. The Na(20)-O(10) bond length is 2.69 Å. The Na(20)-O(11) bond length is 2.48 Å. The Na(20)-O(13) bond length is 2.47 Å. The Na(20)-O(4) bond length is 2.38 Å. The Na(20)-O(8) bond length is 2.71 Å. In the twenty-first Na site, Na(21) is bonded in a 3-coordinate geometry to one O(12), one O(16), one O(3), one O(5), and one O(9) atom. The Na(21)-O(12) bond length is 2.45 Å. The Na(21)-O(16) bond length is 2.45 Å. The Na(21)-O(3) bond length is 2.34 Å. The Na(21)-O(5) bond length is 2.75 Å. The Na(21)-O(9) bond length is 2.75 Å. In the twenty-second Na site, Na(22) is bonded in a 3-coordinate geometry to one O(10), one O(11), one O(15), one O(4), and one O(6) atom. The Na(22)-O(10) bond length is 2.78 Å. The Na(22)-O(11) bond length is 2.43 Å. The Na(22)-O(15) bond length is 2.44 Å. The Na(22)-O(4) bond length is 2.32 Å. The Na(22)-O(6) bond length is 2.77 Å. In the twenty-third Na site, Na(23) is bonded in a 3-coordinate geometry to one O(14), one O(16), one O(3), one O(5), and one O(7) atom. The Na(23)-O(14) bond length is 2.45 Å. The Na(23)-O(16) bond length is 2.47 Å. The Na(23)-O(3) bond length is 2.34 Å. The Na(23)-O(5) bond length is 2.75 Å. The Na(23)-O(7) bond length is 2.74 Å. In the twenty-fourth Na site, Na(24) is bonded in a 3-coordinate geometry to one O(13), one O(15), one O(4), one O(6), and one O(8) atom. The Na(24)-O(13) bond length is 2.48 Å. The Na(24)-O(15) bond length is 2.49 Å. The Na(24)-O(4) bond length is 2.36 Å. The Na(24)-O(6) bond length is 2.72 Å. The Na(24)-O(8) bond length is 2.74 Å. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(10), one O(6), and one O(8) atom to form NiO4 tetrahedra that share corners with two equivalent Na(12)O4 trigonal pyramids, corners with two equivalent Na(6)O4 trigonal pyramids,  an edgeedge with one Na(3)O4 trigonal pyramid, and  an edgeedge with one Na(7)O4 trigonal pyramid. The Ni(1)-O(1) bond length is 1.98 Å. The Ni(1)-O(10) bond length is 2.02 Å. The Ni(1)-O(6) bond length is 2.03 Å. The Ni(1)-O(8) bond length is 2.02 Å. In the second Ni site, Ni(2) is bonded to one O(12), one O(14), one O(16), and one O(4) atom to form NiO4 tetrahedra that share corners with two equivalent Na(2)O4 trigonal pyramids, corners with two equivalent Na(4)O4 trigonal pyramids, corners with two equivalent Na(8)O4 trigonal pyramids,  an edgeedge with one Na(12)O4 trigonal pyramid, and  an edgeedge with one Na(6)O4 trigonal pyramid. The Ni(2)-O(12) bond length is 2.02 Å. The Ni(2)-O(14) bond length is 2.04 Å. The Ni(2)-O(16) bond length is 2.02 Å. The Ni(2)-O(4) bond length is 1.98 Å. In the third Ni site, Ni(3) is bonded to one O(2), one O(5), one O(7), and one O(9) atom to form NiO4 tetrahedra that share corners with two equivalent Na(11)O4 trigonal pyramids, corners with two equivalent Na(5)O4 trigonal pyramids, corners with two equivalent Na(9)O4 trigonal pyramids,  an edgeedge with one Na(2)O4 trigonal pyramid,  an edgeedge with one Na(4)O4 trigonal pyramid, and  an edgeedge with one Na(8)O4 trigonal pyramid. The Ni(3)-O(2) bond length is 1.99 Å. The Ni(3)-O(5) bond length is 2.02 Å. The Ni(3)-O(7) bond length is 2.03 Å. The Ni(3)-O(9) bond length is 2.02 Å. In the fourth Ni site, Ni(4) is bonded to one O(11), one O(13), one O(15), and one O(3) atom to form NiO4 tetrahedra that share corners with two equivalent Na(3)O4 trigonal pyramids, corners with two equivalent Na(7)O4 trigonal pyramids,  an edgeedge with one Na(11)O4 trigonal pyramid,  an edgeedge with one Na(5)O4 trigonal pyramid, and  an edgeedge with one Na(9)O4 trigonal pyramid. The Ni(4)-O(11) bond length is 2.02 Å. The Ni(4)-O(13) bond length is 2.03 Å. The Ni(4)-O(15) bond length is 2.02 Å. The Ni(4)-O(3) bond length is 1.99 Å. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded in a 7-coordinate geometry to one Na(1), one Na(13), one Na(15), one Na(17), one Na(3), one Na(7), and one Ni(1) atom. In the second O site, O(2) is bonded in a 7-coordinate geometry to one Na(14), one Na(16), one Na(18), one Na(2), one Na(4), one Na(8), and one Ni(3) atom. In the third O site, O(3) is bonded in a 7-coordinate geometry to one Na(11), one Na(19), one Na(21), one Na(23), one Na(5), one Na(9), and one Ni(4) atom. In the fourth O site, O(4) is bonded in a 7-coordinate geometry to one Na(10), one Na(12), one Na(20), one Na(22), one Na(24), one Na(6), and one Ni(2) atom. In the fifth O site, O(5) is bonded in a 8-coordinate geometry to one Na(13), one Na(15), one Na(2), one Na(21), one Na(23), one Na(5), one Na(9), and one Ni(3) atom. In the sixth O site, O(6) is bonded in a 8-coordinate geometry to one Na(1), one Na(10), one Na(14), one Na(16), one Na(22), one Na(24), one Na(6), and one Ni(1) atom. In the seventh O site, O(7) is bonded in a 8-coordinate geometry to one Na(11), one Na(13), one Na(17), one Na(19), one Na(23), one Na(4), one Na(5), and one Ni(3) atom. In the eighth O site, O(8) is bonded in a 8-coordinate geometry to one Na(12), one Na(14), one Na(18), one Na(20), one Na(24), one Na(3), one Na(6), and one Ni(1) atom. In the ninth O site, O(9) is bonded in a 8-coordinate geometry to one Na(11), one Na(15), one Na(17), one Na(19), one Na(21), one Na(8), one Na(9), and one Ni(3) atom. In the tenth O site, O(10) is bonded in a 8-coordinate geometry to one Na(10), one Na(12), one Na(16), one Na(18), one Na(20), one Na(22), one Na(7), and one Ni(1) atom. In the eleventh O site, O(11) is bonded in a 8-coordinate geometry to one Na(1), one Na(15), one Na(17), one Na(20), one Na(22), one Na(3), one Na(5), and one Ni(4) atom. In the twelfth O site, O(12) is bonded in a 8-coordinate geometry to one Na(16), one Na(18), one Na(19), one Na(2), one Na(21), one Na(4), one Na(6), and one Ni(2) atom. In the thirteenth O site, O(13) is bonded in a 8-coordinate geometry to one Na(1), one Na(13), one Na(17), one Na(20), one Na(24), one Na(7), one Na(9), and one Ni(4) atom. In the fourteenth O site, O(14) is bonded in a 8-coordinate geometry to one Na(10), one Na(14), one Na(18), one Na(19), one Na(2), one Na(23), one Na(8), and one Ni(2) atom. In the fifteenth O site, O(15) is bonded in a 8-coordinate geometry to one Na(11), one Na(13), one Na(15), one Na(22), one Na(24), one Na(3), one Na(7), and one Ni(4) atom. In the sixteenth O site, O(16) is bonded in a 8-coordinate geometry to one Na(12), one Na(14), one Na(16), one Na(21), one Na(23), one Na(4), one Na(8), and one Ni(2) atom.