Fe(PO3)3 crystallizes in the triclinic P-1 space group. Fe(1) is bonded to one O(1), one O(2), one O(3), one O(4), and one O(8) atom to form FeO5 trigonal bipyramids that share  a cornercorner with one P(2)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(3)O4 tetrahedra. There are three inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(5), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, and corners with two equivalent Fe(1)O5 trigonal bipyramids. In the second P site, P(2) is bonded to one O(3), one O(5), one O(7), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, and  a cornercorner with one Fe(1)O5 trigonal bipyramid. In the third P site, P(3) is bonded to one O(4), one O(6), one O(7), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra, and corners with two equivalent Fe(1)O5 trigonal bipyramids. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Fe(1) and one P(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Fe(1) and one P(2) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Fe(1) and one P(3) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one P(1) and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one P(1) and one P(3) atom. In the seventh O site, O(7) is bonded in a bent 120 degrees geometry to one P(2) and one P(3) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(3) atom. In the ninth O site, O(9) is bonded in a single-bond geometry to one P(2) atom.
Fe(PO3)3 crystallizes in the triclinic P-1 space group. Fe(1) is bonded to one O(1), one O(2), one O(3), one O(4), and one O(8) atom to form FeO5 trigonal bipyramids that share  a cornercorner with one P(2)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(3)O4 tetrahedra. The Fe(1)-O(1) bond length is 1.95 Å. The Fe(1)-O(2) bond length is 1.99 Å. The Fe(1)-O(3) bond length is 1.95 Å. The Fe(1)-O(4) bond length is 2.02 Å. The Fe(1)-O(8) bond length is 1.93 Å. There are three inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(5), and one O(6) atom to form PO4 tetrahedra that share  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, and corners with two equivalent Fe(1)O5 trigonal bipyramids. The P(1)-O(1) bond length is 1.51 Å. The P(1)-O(2) bond length is 1.50 Å. The P(1)-O(5) bond length is 1.58 Å. The P(1)-O(6) bond length is 1.61 Å. In the second P site, P(2) is bonded to one O(3), one O(5), one O(7), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, and  a cornercorner with one Fe(1)O5 trigonal bipyramid. The P(2)-O(3) bond length is 1.54 Å. The P(2)-O(5) bond length is 1.64 Å. The P(2)-O(7) bond length is 1.65 Å. The P(2)-O(9) bond length is 1.46 Å. In the third P site, P(3) is bonded to one O(4), one O(6), one O(7), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(2)O4 tetrahedra, and corners with two equivalent Fe(1)O5 trigonal bipyramids. The P(3)-O(4) bond length is 1.52 Å. The P(3)-O(6) bond length is 1.59 Å. The P(3)-O(7) bond length is 1.60 Å. The P(3)-O(8) bond length is 1.51 Å. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(1) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Fe(1) and one P(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Fe(1) and one P(2) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Fe(1) and one P(3) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one P(1) and one P(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one P(1) and one P(3) atom. In the seventh O site, O(7) is bonded in a bent 120 degrees geometry to one P(2) and one P(3) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one Fe(1) and one P(3) atom. In the ninth O site, O(9) is bonded in a single-bond geometry to one P(2) atom.