Na5P3O10 crystallizes in the monoclinic C2/c space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(4), one O(5), two equivalent O(2), and two equivalent O(3) atoms. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(4), one O(5), and two equivalent O(1) atoms. In the third Na site, Na(3) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(5) atoms to form distorted NaO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra and edges with two equivalent P(1)O4 tetrahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(4), and one O(5) atom to form PO4 tetrahedra that share  a cornercorner with one Na(3)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, and  an edgeedge with one Na(3)O6 octahedra. The corner-sharing octahedral tilt angles are 55°. In the second P site, P(2) is bonded to two equivalent O(3) and two equivalent O(4) atoms to form corner-sharing PO4 tetrahedra. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Na(3), two equivalent Na(2), and one P(1) atom to form distorted corner-sharing ONa3P tetrahedra. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Na(2), one Na(3), two equivalent Na(1), and one P(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Na(2), two equivalent Na(1), and one P(2) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(2), one P(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to one Na(1), one Na(2), one Na(3), and one P(1) atom.
Na5P3O10 crystallizes in the monoclinic C2/c space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(4), one O(5), two equivalent O(2), and two equivalent O(3) atoms. The Na(1)-O(4) bond length is 2.58 Å. The Na(1)-O(5) bond length is 2.35 Å. There is one shorter (2.30 Å) and one longer (2.71 Å) Na(1)-O(2) bond length. There is one shorter (2.27 Å) and one longer (2.35 Å) Na(1)-O(3) bond length. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(4), one O(5), and two equivalent O(1) atoms. The Na(2)-O(2) bond length is 2.34 Å. The Na(2)-O(3) bond length is 2.44 Å. The Na(2)-O(4) bond length is 2.67 Å. The Na(2)-O(5) bond length is 2.43 Å. There is one shorter (2.27 Å) and one longer (2.46 Å) Na(2)-O(1) bond length. In the third Na site, Na(3) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(5) atoms to form distorted NaO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra and edges with two equivalent P(1)O4 tetrahedra. Both Na(3)-O(1) bond lengths are 2.31 Å. Both Na(3)-O(2) bond lengths are 2.72 Å. Both Na(3)-O(5) bond lengths are 2.36 Å. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(4), and one O(5) atom to form PO4 tetrahedra that share  a cornercorner with one Na(3)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, and  an edgeedge with one Na(3)O6 octahedra. The corner-sharing octahedral tilt angles are 55°. The P(1)-O(1) bond length is 1.50 Å. The P(1)-O(2) bond length is 1.52 Å. The P(1)-O(4) bond length is 1.69 Å. The P(1)-O(5) bond length is 1.51 Å. In the second P site, P(2) is bonded to two equivalent O(3) and two equivalent O(4) atoms to form corner-sharing PO4 tetrahedra. Both P(2)-O(3) bond lengths are 1.50 Å. Both P(2)-O(4) bond lengths are 1.59 Å. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Na(3), two equivalent Na(2), and one P(1) atom to form distorted corner-sharing ONa3P tetrahedra. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Na(2), one Na(3), two equivalent Na(1), and one P(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Na(2), two equivalent Na(1), and one P(2) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(2), one P(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to one Na(1), one Na(2), one Na(3), and one P(1) atom.