Na5WO5 crystallizes in the monoclinic C2/c space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form distorted NaO5 square pyramids that share  a cornercorner with one Na(1)O5 square pyramid, corners with three equivalent Na(3)O5 square pyramids, corners with four equivalent Na(2)O5 square pyramids,  a cornercorner with one W(1)O5 trigonal bipyramid,  an edgeedge with one Na(3)O5 square pyramid, edges with two equivalent Na(1)O5 square pyramids, edges with three equivalent Na(2)O5 square pyramids, and edges with two equivalent W(1)O5 trigonal bipyramids. In the second Na site, Na(2) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form NaO5 square pyramids that share  a cornercorner with one Na(2)O5 square pyramid,  a cornercorner with one Na(3)O5 square pyramid, corners with four equivalent Na(1)O5 square pyramids, corners with three equivalent W(1)O5 trigonal bipyramids, edges with two equivalent Na(2)O5 square pyramids, edges with two equivalent Na(3)O5 square pyramids, edges with three equivalent Na(1)O5 square pyramids, and  an edgeedge with one W(1)O5 trigonal bipyramid. In the third Na site, Na(3) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form NaO5 square pyramids that share corners with two equivalent Na(2)O5 square pyramids, corners with six equivalent Na(1)O5 square pyramids,  a cornercorner with one W(1)O5 trigonal bipyramid, edges with two equivalent Na(1)O5 square pyramids, edges with four equivalent Na(2)O5 square pyramids, and edges with two equivalent W(1)O5 trigonal bipyramids. W(1) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form WO5 trigonal bipyramids that share  a cornercorner with one Na(3)O5 square pyramid, corners with two equivalent Na(1)O5 square pyramids, corners with six equivalent Na(2)O5 square pyramids, edges with two equivalent Na(2)O5 square pyramids, edges with two equivalent Na(3)O5 square pyramids, and edges with four equivalent Na(1)O5 square pyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Na(3), two equivalent Na(1), two equivalent Na(2), and one W(1) atom to form a mixture of distorted edge and corner-sharing ONa5W octahedra. The corner-sharing octahedral tilt angles range from 6-22°. In the second O site, O(2) is bonded to one Na(3), two equivalent Na(1), two equivalent Na(2), and one W(1) atom to form a mixture of edge and corner-sharing ONa5W octahedra. The corner-sharing octahedral tilt angles range from 8-22°. In the third O site, O(3) is bonded to one Na(3), two equivalent Na(1), two equivalent Na(2), and one W(1) atom to form a mixture of distorted edge and corner-sharing ONa5W octahedra. The corner-sharing octahedral tilt angles range from 11-17°.
Na5WO5 crystallizes in the monoclinic C2/c space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form distorted NaO5 square pyramids that share  a cornercorner with one Na(1)O5 square pyramid, corners with three equivalent Na(3)O5 square pyramids, corners with four equivalent Na(2)O5 square pyramids,  a cornercorner with one W(1)O5 trigonal bipyramid,  an edgeedge with one Na(3)O5 square pyramid, edges with two equivalent Na(1)O5 square pyramids, edges with three equivalent Na(2)O5 square pyramids, and edges with two equivalent W(1)O5 trigonal bipyramids. The Na(1)-O(3) bond length is 2.37 Å. There is one shorter (2.34 Å) and one longer (2.75 Å) Na(1)-O(1) bond length. There is one shorter (2.34 Å) and one longer (2.42 Å) Na(1)-O(2) bond length. In the second Na site, Na(2) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form NaO5 square pyramids that share  a cornercorner with one Na(2)O5 square pyramid,  a cornercorner with one Na(3)O5 square pyramid, corners with four equivalent Na(1)O5 square pyramids, corners with three equivalent W(1)O5 trigonal bipyramids, edges with two equivalent Na(2)O5 square pyramids, edges with two equivalent Na(3)O5 square pyramids, edges with three equivalent Na(1)O5 square pyramids, and  an edgeedge with one W(1)O5 trigonal bipyramid. The Na(2)-O(3) bond length is 2.42 Å. There is one shorter (2.39 Å) and one longer (2.54 Å) Na(2)-O(1) bond length. There is one shorter (2.43 Å) and one longer (2.53 Å) Na(2)-O(2) bond length. In the third Na site, Na(3) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form NaO5 square pyramids that share corners with two equivalent Na(2)O5 square pyramids, corners with six equivalent Na(1)O5 square pyramids,  a cornercorner with one W(1)O5 trigonal bipyramid, edges with two equivalent Na(1)O5 square pyramids, edges with four equivalent Na(2)O5 square pyramids, and edges with two equivalent W(1)O5 trigonal bipyramids. The Na(3)-O(3) bond length is 2.54 Å. Both Na(3)-O(1) bond lengths are 2.32 Å. Both Na(3)-O(2) bond lengths are 2.32 Å. W(1) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form WO5 trigonal bipyramids that share  a cornercorner with one Na(3)O5 square pyramid, corners with two equivalent Na(1)O5 square pyramids, corners with six equivalent Na(2)O5 square pyramids, edges with two equivalent Na(2)O5 square pyramids, edges with two equivalent Na(3)O5 square pyramids, and edges with four equivalent Na(1)O5 square pyramids. The W(1)-O(3) bond length is 1.91 Å. Both W(1)-O(1) bond lengths are 1.94 Å. Both W(1)-O(2) bond lengths are 1.96 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Na(3), two equivalent Na(1), two equivalent Na(2), and one W(1) atom to form a mixture of distorted edge and corner-sharing ONa5W octahedra. The corner-sharing octahedral tilt angles range from 6-22°. In the second O site, O(2) is bonded to one Na(3), two equivalent Na(1), two equivalent Na(2), and one W(1) atom to form a mixture of edge and corner-sharing ONa5W octahedra. The corner-sharing octahedral tilt angles range from 8-22°. In the third O site, O(3) is bonded to one Na(3), two equivalent Na(1), two equivalent Na(2), and one W(1) atom to form a mixture of distorted edge and corner-sharing ONa5W octahedra. The corner-sharing octahedral tilt angles range from 11-17°.