Sn3P3O13 crystallizes in the monoclinic P2_1/m space group. There are three inequivalent Sn sites. In the first Sn site, Sn(1) is bonded to one O(1), one O(5), one O(6), one O(9), and two equivalent O(8) atoms to form SnO6 octahedra that share corners with two equivalent Sn(3)O6 octahedra,  a cornercorner with one Sn(2)O5 square pyramid,  a cornercorner with one P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and  an edgeedge with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles are 53°. In the second Sn site, Sn(2) is bonded to one O(1), one O(3), one O(7), and two equivalent O(2) atoms to form SnO5 square pyramids that share  a cornercorner with one Sn(1)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, and corners with three equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. In the third Sn site, Sn(3) is bonded to two equivalent O(10), two equivalent O(4), and two equivalent O(6) atoms to form SnO6 octahedra that share corners with two equivalent Sn(1)O6 octahedra, corners with two equivalent P(2)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra, and edges with two equivalent Sn(3)O6 octahedra. The corner-sharing octahedral tilt angles are 53°. There are three inequivalent P sites. In the first P site, P(1) is bonded to one O(5), one O(7), and two equivalent O(2) atoms to form PO4 tetrahedra that share  a cornercorner with one Sn(1)O6 octahedra and corners with three equivalent Sn(2)O5 square pyramids. The corner-sharing octahedral tilt angles are 41°. In the second P site, P(2) is bonded to one O(10), one O(3), and two equivalent O(8) atoms to form PO4 tetrahedra that share corners with two equivalent Sn(1)O6 octahedra, corners with two equivalent Sn(3)O6 octahedra, and  a cornercorner with one Sn(2)O5 square pyramid. The corner-sharing octahedral tilt angles range from 35-54°. In the third P site, P(3) is bonded to one O(1), one O(9), and two equivalent O(4) atoms to form PO4 tetrahedra that share corners with two equivalent Sn(3)O6 octahedra,  a cornercorner with one Sn(2)O5 square pyramid, and  an edgeedge with one Sn(1)O6 octahedra. The corner-sharing octahedral tilt angles are 47°. There are ten inequivalent O sites. In the first O site, O(10) is bonded in a distorted trigonal planar geometry to two equivalent Sn(3) and one P(2) atom. In the second O site, O(1) is bonded in a 3-coordinate geometry to one Sn(1), one Sn(2), and one P(3) atom. In the third O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Sn(2) and one P(1) atom. In the fourth O site, O(3) is bonded in a bent 150 degrees geometry to one Sn(2) and one P(2) atom. In the fifth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Sn(3) and one P(3) atom. In the sixth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one Sn(1) and one P(1) atom. In the seventh O site, O(6) is bonded in a trigonal planar geometry to one Sn(1) and two equivalent Sn(3) atoms. In the eighth O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Sn(2) and one P(1) atom. In the ninth O site, O(8) is bonded in a bent 150 degrees geometry to one Sn(1) and one P(2) atom. In the tenth O site, O(9) is bonded in a water-like geometry to one Sn(1) and one P(3) atom.
Sn3P3O13 crystallizes in the monoclinic P2_1/m space group. There are three inequivalent Sn sites. In the first Sn site, Sn(1) is bonded to one O(1), one O(5), one O(6), one O(9), and two equivalent O(8) atoms to form SnO6 octahedra that share corners with two equivalent Sn(3)O6 octahedra,  a cornercorner with one Sn(2)O5 square pyramid,  a cornercorner with one P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and  an edgeedge with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles are 53°. The Sn(1)-O(1) bond length is 2.25 Å. The Sn(1)-O(5) bond length is 2.04 Å. The Sn(1)-O(6) bond length is 2.08 Å. The Sn(1)-O(9) bond length is 2.08 Å. Both Sn(1)-O(8) bond lengths are 2.07 Å. In the second Sn site, Sn(2) is bonded to one O(1), one O(3), one O(7), and two equivalent O(2) atoms to form SnO5 square pyramids that share  a cornercorner with one Sn(1)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, and corners with three equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. The Sn(2)-O(1) bond length is 2.25 Å. The Sn(2)-O(3) bond length is 2.20 Å. The Sn(2)-O(7) bond length is 2.10 Å. Both Sn(2)-O(2) bond lengths are 2.11 Å. In the third Sn site, Sn(3) is bonded to two equivalent O(10), two equivalent O(4), and two equivalent O(6) atoms to form SnO6 octahedra that share corners with two equivalent Sn(1)O6 octahedra, corners with two equivalent P(2)O4 tetrahedra, corners with two equivalent P(3)O4 tetrahedra, and edges with two equivalent Sn(3)O6 octahedra. The corner-sharing octahedral tilt angles are 53°. Both Sn(3)-O(10) bond lengths are 2.18 Å. Both Sn(3)-O(4) bond lengths are 2.06 Å. Both Sn(3)-O(6) bond lengths are 2.11 Å. There are three inequivalent P sites. In the first P site, P(1) is bonded to one O(5), one O(7), and two equivalent O(2) atoms to form PO4 tetrahedra that share  a cornercorner with one Sn(1)O6 octahedra and corners with three equivalent Sn(2)O5 square pyramids. The corner-sharing octahedral tilt angles are 41°. The P(1)-O(5) bond length is 1.57 Å. The P(1)-O(7) bond length is 1.56 Å. Both P(1)-O(2) bond lengths are 1.55 Å. In the second P site, P(2) is bonded to one O(10), one O(3), and two equivalent O(8) atoms to form PO4 tetrahedra that share corners with two equivalent Sn(1)O6 octahedra, corners with two equivalent Sn(3)O6 octahedra, and  a cornercorner with one Sn(2)O5 square pyramid. The corner-sharing octahedral tilt angles range from 35-54°. The P(2)-O(10) bond length is 1.64 Å. The P(2)-O(3) bond length is 1.52 Å. Both P(2)-O(8) bond lengths are 1.53 Å. In the third P site, P(3) is bonded to one O(1), one O(9), and two equivalent O(4) atoms to form PO4 tetrahedra that share corners with two equivalent Sn(3)O6 octahedra,  a cornercorner with one Sn(2)O5 square pyramid, and  an edgeedge with one Sn(1)O6 octahedra. The corner-sharing octahedral tilt angles are 47°. The P(3)-O(1) bond length is 1.59 Å. The P(3)-O(9) bond length is 1.56 Å. Both P(3)-O(4) bond lengths are 1.55 Å. There are ten inequivalent O sites. In the first O site, O(10) is bonded in a distorted trigonal planar geometry to two equivalent Sn(3) and one P(2) atom. In the second O site, O(1) is bonded in a 3-coordinate geometry to one Sn(1), one Sn(2), and one P(3) atom. In the third O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Sn(2) and one P(1) atom. In the fourth O site, O(3) is bonded in a bent 150 degrees geometry to one Sn(2) and one P(2) atom. In the fifth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Sn(3) and one P(3) atom. In the sixth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one Sn(1) and one P(1) atom. In the seventh O site, O(6) is bonded in a trigonal planar geometry to one Sn(1) and two equivalent Sn(3) atoms. In the eighth O site, O(7) is bonded in a distorted bent 120 degrees geometry to one Sn(2) and one P(1) atom. In the ninth O site, O(8) is bonded in a bent 150 degrees geometry to one Sn(1) and one P(2) atom. In the tenth O site, O(9) is bonded in a water-like geometry to one Sn(1) and one P(3) atom.