Na2VPO6 crystallizes in the orthorhombic Pna2_1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. In the second Na site, Na(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form distorted NaO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra and  an edgeedge with one P(1)O4 tetrahedra. V(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. P(1) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form PO4 tetrahedra that share corners with two equivalent Na(2)O6 octahedra and  an edgeedge with one Na(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 58-67°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Na(1), one Na(2), and one V(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Na(1), one Na(2), and one V(1) atom. In the third O site, O(3) is bonded to one Na(1), one Na(2), one V(1), and one P(1) atom to form a mixture of distorted edge and corner-sharing ONa2VP tetrahedra. In the fourth O site, O(4) is bonded to one Na(1), one Na(2), one V(1), and one P(1) atom to form a mixture of edge and corner-sharing ONa2VP tetrahedra. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(2), one V(1), and one P(1) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one V(1), and one P(1) atom.
Na2VPO6 crystallizes in the orthorhombic Pna2_1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. The Na(1)-O(1) bond length is 2.28 Å. The Na(1)-O(2) bond length is 2.22 Å. The Na(1)-O(3) bond length is 2.40 Å. The Na(1)-O(4) bond length is 2.27 Å. The Na(1)-O(5) bond length is 2.64 Å. The Na(1)-O(6) bond length is 2.83 Å. In the second Na site, Na(2) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form distorted NaO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra and  an edgeedge with one P(1)O4 tetrahedra. The Na(2)-O(1) bond length is 2.38 Å. The Na(2)-O(2) bond length is 2.43 Å. The Na(2)-O(3) bond length is 2.32 Å. The Na(2)-O(4) bond length is 2.23 Å. The Na(2)-O(5) bond length is 2.44 Å. The Na(2)-O(6) bond length is 2.55 Å. V(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. The V(1)-O(1) bond length is 1.67 Å. The V(1)-O(2) bond length is 1.66 Å. The V(1)-O(3) bond length is 2.09 Å. The V(1)-O(4) bond length is 2.21 Å. The V(1)-O(5) bond length is 2.43 Å. The V(1)-O(6) bond length is 2.00 Å. P(1) is bonded to one O(3), one O(4), one O(5), and one O(6) atom to form PO4 tetrahedra that share corners with two equivalent Na(2)O6 octahedra and  an edgeedge with one Na(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 58-67°. The P(1)-O(3) bond length is 1.58 Å. The P(1)-O(4) bond length is 1.56 Å. The P(1)-O(5) bond length is 1.52 Å. The P(1)-O(6) bond length is 1.58 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Na(1), one Na(2), and one V(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Na(1), one Na(2), and one V(1) atom. In the third O site, O(3) is bonded to one Na(1), one Na(2), one V(1), and one P(1) atom to form a mixture of distorted edge and corner-sharing ONa2VP tetrahedra. In the fourth O site, O(4) is bonded to one Na(1), one Na(2), one V(1), and one P(1) atom to form a mixture of edge and corner-sharing ONa2VP tetrahedra. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(2), one V(1), and one P(1) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one V(1), and one P(1) atom.