Na6MgV2O8 crystallizes in the triclinic P1 space group. There are six inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1), one O(2), one O(4), and one O(7) atom to form NaO4 tetrahedra that share corners with two equivalent Mg(1)O5 square pyramids, corners with two equivalent Na(3)O4 tetrahedra, corners with two equivalent Na(5)O4 tetrahedra, corners with two equivalent V(1)O4 tetrahedra, and corners with two equivalent V(2)O4 tetrahedra. In the second Na site, Na(2) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(3), one O(4), and one O(5) atom. In the third Na site, Na(3) is bonded to one O(2), one O(3), one O(4), and one O(6) atom to form NaO4 tetrahedra that share corners with two equivalent Mg(1)O5 square pyramids, corners with two equivalent Na(1)O4 tetrahedra, corners with two equivalent Na(5)O4 tetrahedra, corners with two equivalent V(1)O4 tetrahedra, and corners with two equivalent V(2)O4 tetrahedra. In the fourth Na site, Na(4) is bonded in a distorted rectangular see-saw-like geometry to one O(3), one O(5), one O(6), and one O(8) atom. In the fifth Na site, Na(5) is bonded to one O(2), one O(6), one O(7), and one O(8) atom to form NaO4 tetrahedra that share corners with two equivalent Mg(1)O5 square pyramids, corners with two equivalent Na(1)O4 tetrahedra, corners with two equivalent Na(3)O4 tetrahedra, corners with two equivalent V(1)O4 tetrahedra, and corners with two equivalent V(2)O4 tetrahedra. In the sixth Na site, Na(6) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(5), one O(7), and one O(8) atom. Mg(1) is bonded to one O(3), one O(4), one O(5), one O(7), and one O(8) atom to form distorted MgO5 square pyramids that share  a cornercorner with one V(2)O4 tetrahedra, corners with two equivalent Na(1)O4 tetrahedra, corners with two equivalent Na(3)O4 tetrahedra, corners with two equivalent Na(5)O4 tetrahedra, corners with two equivalent V(1)O4 tetrahedra, and  an edgeedge with one V(2)O4 tetrahedra. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(1), one O(2), one O(3), and one O(8) atom to form VO4 tetrahedra that share corners with two equivalent Mg(1)O5 square pyramids, corners with two equivalent Na(1)O4 tetrahedra, corners with two equivalent Na(3)O4 tetrahedra, and corners with two equivalent Na(5)O4 tetrahedra. In the second V site, V(2) is bonded to one O(4), one O(5), one O(6), and one O(7) atom to form VO4 tetrahedra that share  a cornercorner with one Mg(1)O5 square pyramid, corners with two equivalent Na(1)O4 tetrahedra, corners with two equivalent Na(3)O4 tetrahedra, corners with two equivalent Na(5)O4 tetrahedra, and  an edgeedge with one Mg(1)O5 square pyramid. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(2), one Na(6), and one V(1) atom. In the second O site, O(2) is bonded to one Na(1), one Na(3), one Na(5), and one V(1) atom to form ONa3V tetrahedra that share corners with two equivalent O(6)Na3V tetrahedra, corners with two equivalent O(3)Na3MgV trigonal bipyramids, corners with two equivalent O(4)Na3MgV trigonal bipyramids, corners with two equivalent O(7)Na3MgV trigonal bipyramids, and corners with two equivalent O(8)Na3MgV trigonal bipyramids. In the third O site, O(3) is bonded to one Na(2), one Na(3), one Na(4), one Mg(1), and one V(1) atom to form distorted ONa3MgV trigonal bipyramids that share corners with two equivalent O(2)Na3V tetrahedra, corners with two equivalent O(6)Na3V tetrahedra,  a cornercorner with one O(4)Na3MgV trigonal bipyramid,  a cornercorner with one O(5)Na3MgV trigonal bipyramid,  a cornercorner with one O(7)Na3MgV trigonal bipyramid,  a cornercorner with one O(8)Na3MgV trigonal bipyramid,  an edgeedge with one O(4)Na3MgV trigonal bipyramid,  an edgeedge with one O(5)Na3MgV trigonal bipyramid, and  an edgeedge with one O(8)Na3MgV trigonal bipyramid. In the fourth O site, O(4) is bonded to one Na(1), one Na(2), one Na(3), one Mg(1), and one V(2) atom to form distorted ONa3MgV trigonal bipyramids that share corners with two equivalent O(2)Na3V tetrahedra, corners with two equivalent O(6)Na3V tetrahedra,  a cornercorner with one O(3)Na3MgV trigonal bipyramid,  a cornercorner with one O(5)Na3MgV trigonal bipyramid,  a cornercorner with one O(7)Na3MgV trigonal bipyramid,  a cornercorner with one O(8)Na3MgV trigonal bipyramid,  an edgeedge with one O(3)Na3MgV trigonal bipyramid,  an edgeedge with one O(5)Na3MgV trigonal bipyramid, and  an edgeedge with one O(7)Na3MgV trigonal bipyramid. In the fifth O site, O(5) is bonded to one Na(2), one Na(4), one Na(6), one Mg(1), and one V(2) atom to form distorted ONa3MgV trigonal bipyramids that share corners with two equivalent O(6)Na3V tetrahedra,  a cornercorner with one O(3)Na3MgV trigonal bipyramid,  a cornercorner with one O(4)Na3MgV trigonal bipyramid,  a cornercorner with one O(7)Na3MgV trigonal bipyramid,  a cornercorner with one O(8)Na3MgV trigonal bipyramid,  an edgeedge with one O(3)Na3MgV trigonal bipyramid,  an edgeedge with one O(4)Na3MgV trigonal bipyramid,  an edgeedge with one O(7)Na3MgV trigonal bipyramid, and  an edgeedge with one O(8)Na3MgV trigonal bipyramid. In the sixth O site, O(6) is bonded to one Na(3), one Na(4), one Na(5), and one V(2) atom to form distorted ONa3V tetrahedra that share corners with two equivalent O(2)Na3V tetrahedra, corners with two equivalent O(3)Na3MgV trigonal bipyramids, corners with two equivalent O(4)Na3MgV trigonal bipyramids, corners with two equivalent O(5)Na3MgV trigonal bipyramids, corners with two equivalent O(7)Na3MgV trigonal bipyramids, and corners with two equivalent O(8)Na3MgV trigonal bipyramids. In the seventh O site, O(7) is bonded to one Na(1), one Na(5), one Na(6), one Mg(1), and one V(2) atom to form distorted ONa3MgV trigonal bipyramids that share corners with two equivalent O(2)Na3V tetrahedra, corners with two equivalent O(6)Na3V tetrahedra,  a cornercorner with one O(3)Na3MgV trigonal bipyramid,  a cornercorner with one O(4)Na3MgV trigonal bipyramid,  a cornercorner with one O(5)Na3MgV trigonal bipyramid,  a cornercorner with one O(8)Na3MgV trigonal bipyramid,  an edgeedge with one O(4)Na3MgV trigonal bipyramid,  an edgeedge with one O(5)Na3MgV trigonal bipyramid, and  an edgeedge with one O(8)Na3MgV trigonal bipyramid. In the eighth O site, O(8) is bonded to one Na(4), one Na(5), one Na(6), one Mg(1), and one V(1) atom to form distorted ONa3MgV trigonal bipyramids that share corners with two equivalent O(2)Na3V tetrahedra, corners with two equivalent O(6)Na3V tetrahedra,  a cornercorner with one O(3)Na3MgV trigonal bipyramid,  a cornercorner with one O(4)Na3MgV trigonal bipyramid,  a cornercorner with one O(5)Na3MgV trigonal bipyramid,  a cornercorner with one O(7)Na3MgV trigonal bipyramid,  an edgeedge with one O(3)Na3MgV trigonal bipyramid,  an edgeedge with one O(5)Na3MgV trigonal bipyramid, and  an edgeedge with one O(7)Na3MgV trigonal bipyramid.
Na6MgV2O8 crystallizes in the triclinic P1 space group. There are six inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1), one O(2), one O(4), and one O(7) atom to form NaO4 tetrahedra that share corners with two equivalent Mg(1)O5 square pyramids, corners with two equivalent Na(3)O4 tetrahedra, corners with two equivalent Na(5)O4 tetrahedra, corners with two equivalent V(1)O4 tetrahedra, and corners with two equivalent V(2)O4 tetrahedra. The Na(1)-O(1) bond length is 2.32 Å. The Na(1)-O(2) bond length is 2.24 Å. The Na(1)-O(4) bond length is 2.48 Å. The Na(1)-O(7) bond length is 2.47 Å. In the second Na site, Na(2) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(3), one O(4), and one O(5) atom. The Na(2)-O(1) bond length is 2.20 Å. The Na(2)-O(3) bond length is 2.34 Å. The Na(2)-O(4) bond length is 2.33 Å. The Na(2)-O(5) bond length is 2.23 Å. In the third Na site, Na(3) is bonded to one O(2), one O(3), one O(4), and one O(6) atom to form NaO4 tetrahedra that share corners with two equivalent Mg(1)O5 square pyramids, corners with two equivalent Na(1)O4 tetrahedra, corners with two equivalent Na(5)O4 tetrahedra, corners with two equivalent V(1)O4 tetrahedra, and corners with two equivalent V(2)O4 tetrahedra. The Na(3)-O(2) bond length is 2.22 Å. The Na(3)-O(3) bond length is 2.38 Å. The Na(3)-O(4) bond length is 2.43 Å. The Na(3)-O(6) bond length is 2.33 Å. In the fourth Na site, Na(4) is bonded in a distorted rectangular see-saw-like geometry to one O(3), one O(5), one O(6), and one O(8) atom. The Na(4)-O(3) bond length is 2.45 Å. The Na(4)-O(5) bond length is 2.33 Å. The Na(4)-O(6) bond length is 2.40 Å. The Na(4)-O(8) bond length is 2.45 Å. In the fifth Na site, Na(5) is bonded to one O(2), one O(6), one O(7), and one O(8) atom to form NaO4 tetrahedra that share corners with two equivalent Mg(1)O5 square pyramids, corners with two equivalent Na(1)O4 tetrahedra, corners with two equivalent Na(3)O4 tetrahedra, corners with two equivalent V(1)O4 tetrahedra, and corners with two equivalent V(2)O4 tetrahedra. The Na(5)-O(2) bond length is 2.23 Å. The Na(5)-O(6) bond length is 2.32 Å. The Na(5)-O(7) bond length is 2.44 Å. The Na(5)-O(8) bond length is 2.37 Å. In the sixth Na site, Na(6) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(5), one O(7), and one O(8) atom. The Na(6)-O(1) bond length is 2.20 Å. The Na(6)-O(5) bond length is 2.23 Å. The Na(6)-O(7) bond length is 2.33 Å. The Na(6)-O(8) bond length is 2.35 Å. Mg(1) is bonded to one O(3), one O(4), one O(5), one O(7), and one O(8) atom to form distorted MgO5 square pyramids that share  a cornercorner with one V(2)O4 tetrahedra, corners with two equivalent Na(1)O4 tetrahedra, corners with two equivalent Na(3)O4 tetrahedra, corners with two equivalent Na(5)O4 tetrahedra, corners with two equivalent V(1)O4 tetrahedra, and  an edgeedge with one V(2)O4 tetrahedra. The Mg(1)-O(3) bond length is 2.16 Å. The Mg(1)-O(4) bond length is 2.14 Å. The Mg(1)-O(5) bond length is 2.10 Å. The Mg(1)-O(7) bond length is 2.15 Å. The Mg(1)-O(8) bond length is 2.15 Å. There are two inequivalent V sites. In the first V site, V(1) is bonded to one O(1), one O(2), one O(3), and one O(8) atom to form VO4 tetrahedra that share corners with two equivalent Mg(1)O5 square pyramids, corners with two equivalent Na(1)O4 tetrahedra, corners with two equivalent Na(3)O4 tetrahedra, and corners with two equivalent Na(5)O4 tetrahedra. The V(1)-O(1) bond length is 1.82 Å. The V(1)-O(2) bond length is 1.76 Å. The V(1)-O(3) bond length is 1.92 Å. The V(1)-O(8) bond length is 1.92 Å. In the second V site, V(2) is bonded to one O(4), one O(5), one O(6), and one O(7) atom to form VO4 tetrahedra that share  a cornercorner with one Mg(1)O5 square pyramid, corners with two equivalent Na(1)O4 tetrahedra, corners with two equivalent Na(3)O4 tetrahedra, corners with two equivalent Na(5)O4 tetrahedra, and  an edgeedge with one Mg(1)O5 square pyramid. The V(2)-O(4) bond length is 1.86 Å. The V(2)-O(5) bond length is 1.84 Å. The V(2)-O(6) bond length is 1.77 Å. The V(2)-O(7) bond length is 1.86 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(2), one Na(6), and one V(1) atom. In the second O site, O(2) is bonded to one Na(1), one Na(3), one Na(5), and one V(1) atom to form ONa3V tetrahedra that share corners with two equivalent O(6)Na3V tetrahedra, corners with two equivalent O(3)Na3MgV trigonal bipyramids, corners with two equivalent O(4)Na3MgV trigonal bipyramids, corners with two equivalent O(7)Na3MgV trigonal bipyramids, and corners with two equivalent O(8)Na3MgV trigonal bipyramids. In the third O site, O(3) is bonded to one Na(2), one Na(3), one Na(4), one Mg(1), and one V(1) atom to form distorted ONa3MgV trigonal bipyramids that share corners with two equivalent O(2)Na3V tetrahedra, corners with two equivalent O(6)Na3V tetrahedra,  a cornercorner with one O(4)Na3MgV trigonal bipyramid,  a cornercorner with one O(5)Na3MgV trigonal bipyramid,  a cornercorner with one O(7)Na3MgV trigonal bipyramid,  a cornercorner with one O(8)Na3MgV trigonal bipyramid,  an edgeedge with one O(4)Na3MgV trigonal bipyramid,  an edgeedge with one O(5)Na3MgV trigonal bipyramid, and  an edgeedge with one O(8)Na3MgV trigonal bipyramid. In the fourth O site, O(4) is bonded to one Na(1), one Na(2), one Na(3), one Mg(1), and one V(2) atom to form distorted ONa3MgV trigonal bipyramids that share corners with two equivalent O(2)Na3V tetrahedra, corners with two equivalent O(6)Na3V tetrahedra,  a cornercorner with one O(3)Na3MgV trigonal bipyramid,  a cornercorner with one O(5)Na3MgV trigonal bipyramid,  a cornercorner with one O(7)Na3MgV trigonal bipyramid,  a cornercorner with one O(8)Na3MgV trigonal bipyramid,  an edgeedge with one O(3)Na3MgV trigonal bipyramid,  an edgeedge with one O(5)Na3MgV trigonal bipyramid, and  an edgeedge with one O(7)Na3MgV trigonal bipyramid. In the fifth O site, O(5) is bonded to one Na(2), one Na(4), one Na(6), one Mg(1), and one V(2) atom to form distorted ONa3MgV trigonal bipyramids that share corners with two equivalent O(6)Na3V tetrahedra,  a cornercorner with one O(3)Na3MgV trigonal bipyramid,  a cornercorner with one O(4)Na3MgV trigonal bipyramid,  a cornercorner with one O(7)Na3MgV trigonal bipyramid,  a cornercorner with one O(8)Na3MgV trigonal bipyramid,  an edgeedge with one O(3)Na3MgV trigonal bipyramid,  an edgeedge with one O(4)Na3MgV trigonal bipyramid,  an edgeedge with one O(7)Na3MgV trigonal bipyramid, and  an edgeedge with one O(8)Na3MgV trigonal bipyramid. In the sixth O site, O(6) is bonded to one Na(3), one Na(4), one Na(5), and one V(2) atom to form distorted ONa3V tetrahedra that share corners with two equivalent O(2)Na3V tetrahedra, corners with two equivalent O(3)Na3MgV trigonal bipyramids, corners with two equivalent O(4)Na3MgV trigonal bipyramids, corners with two equivalent O(5)Na3MgV trigonal bipyramids, corners with two equivalent O(7)Na3MgV trigonal bipyramids, and corners with two equivalent O(8)Na3MgV trigonal bipyramids. In the seventh O site, O(7) is bonded to one Na(1), one Na(5), one Na(6), one Mg(1), and one V(2) atom to form distorted ONa3MgV trigonal bipyramids that share corners with two equivalent O(2)Na3V tetrahedra, corners with two equivalent O(6)Na3V tetrahedra,  a cornercorner with one O(3)Na3MgV trigonal bipyramid,  a cornercorner with one O(4)Na3MgV trigonal bipyramid,  a cornercorner with one O(5)Na3MgV trigonal bipyramid,  a cornercorner with one O(8)Na3MgV trigonal bipyramid,  an edgeedge with one O(4)Na3MgV trigonal bipyramid,  an edgeedge with one O(5)Na3MgV trigonal bipyramid, and  an edgeedge with one O(8)Na3MgV trigonal bipyramid. In the eighth O site, O(8) is bonded to one Na(4), one Na(5), one Na(6), one Mg(1), and one V(1) atom to form distorted ONa3MgV trigonal bipyramids that share corners with two equivalent O(2)Na3V tetrahedra, corners with two equivalent O(6)Na3V tetrahedra,  a cornercorner with one O(3)Na3MgV trigonal bipyramid,  a cornercorner with one O(4)Na3MgV trigonal bipyramid,  a cornercorner with one O(5)Na3MgV trigonal bipyramid,  a cornercorner with one O(7)Na3MgV trigonal bipyramid,  an edgeedge with one O(3)Na3MgV trigonal bipyramid,  an edgeedge with one O(5)Na3MgV trigonal bipyramid, and  an edgeedge with one O(7)Na3MgV trigonal bipyramid.