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 4-coordinate geometry to one O(1), one O(5), and two equivalent O(4) atoms. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(4), one O(5), and two equivalent O(3) atoms. In the third Na site, Na(3) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form NaO6 octahedra that share corners with six 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 corners with three equivalent Na(3)O6 octahedra and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 18-56°. In the second P site, P(2) is bonded to two equivalent O(2) and two equivalent O(3) atoms to form corner-sharing PO4 tetrahedra. There are five 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(3), and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Na(2), one P(1), and one P(2) atom. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Na(2) and one P(2) atom. In the fourth O site, O(4) is bonded in a 1-coordinate geometry to one Na(2), one Na(3), two equivalent Na(1), and one P(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate 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 4-coordinate geometry to one O(1), one O(5), and two equivalent O(4) atoms. The Na(1)-O(1) bond length is 2.32 Å. The Na(1)-O(5) bond length is 2.29 Å. There is one shorter (2.36 Å) and one longer (2.51 Å) Na(1)-O(4) bond length. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(4), one O(5), and two equivalent O(3) atoms. The Na(2)-O(1) bond length is 2.31 Å. The Na(2)-O(2) bond length is 2.59 Å. The Na(2)-O(4) bond length is 2.95 Å. The Na(2)-O(5) bond length is 2.37 Å. There is one shorter (2.29 Å) and one longer (2.34 Å) Na(2)-O(3) bond length. In the third Na site, Na(3) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form NaO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra. Both Na(3)-O(1) bond lengths are 2.32 Å. Both Na(3)-O(4) bond lengths are 2.40 Å. Both Na(3)-O(5) bond lengths are 2.33 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 corners with three equivalent Na(3)O6 octahedra and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 18-56°. The P(1)-O(1) bond length is 1.51 Å. The P(1)-O(2) bond length is 1.65 Å. The P(1)-O(4) bond length is 1.52 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(2) and two equivalent O(3) atoms to form corner-sharing PO4 tetrahedra. Both P(2)-O(2) bond lengths are 1.60 Å. Both P(2)-O(3) bond lengths are 1.49 Å. There are five 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(3), and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Na(2), one P(1), and one P(2) atom. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Na(2) and one P(2) atom. In the fourth O site, O(4) is bonded in a 1-coordinate geometry to one Na(2), one Na(3), two equivalent Na(1), and one P(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Na(3), and one P(1) atom.