Sn(PO3)3 crystallizes in the trigonal P312 space group. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded to six equivalent O(2) atoms to form SnO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra. In the second Sn site, Sn(2) is bonded to six equivalent O(3) atoms to form SnO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra. P(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form PO4 tetrahedra that share  a cornercorner with one Sn(1)O6 octahedra,  a cornercorner with one Sn(2)O6 octahedra, and corners with two equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 36-40°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to two equivalent P(1) atoms. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Sn(1) and one P(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Sn(2) and one P(1) atom.
Sn(PO3)3 crystallizes in the trigonal P312 space group. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded to six equivalent O(2) atoms to form SnO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra. All Sn(1)-O(2) bond lengths are 2.47 Å. In the second Sn site, Sn(2) is bonded to six equivalent O(3) atoms to form SnO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra. All Sn(2)-O(3) bond lengths are 2.03 Å. P(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form PO4 tetrahedra that share  a cornercorner with one Sn(1)O6 octahedra,  a cornercorner with one Sn(2)O6 octahedra, and corners with two equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 36-40°. The P(1)-O(2) bond length is 1.47 Å. The P(1)-O(3) bond length is 1.51 Å. There is one shorter (1.59 Å) and one longer (1.60 Å) P(1)-O(1) bond length. There are three inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to two equivalent P(1) atoms. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Sn(1) and one P(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Sn(2) and one P(1) atom.