Fe7(PO5)4 crystallizes in the triclinic P-1 space group. There are five inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(10), one O(2), one O(5), one O(6), and one O(7) atom to form FeO6 octahedra that share  a cornercorner with one Fe(2)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra,  a faceface with one Fe(4)O6 octahedra, and  a faceface with one Fe(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-54°. In the second Fe site, Fe(2) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form FeO6 octahedra that share corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Fe(5)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and faces with two equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 53-58°. In the third Fe site, Fe(3) is bonded to one O(1), one O(3), one O(4), one O(7), one O(8), and one O(9) atom to form distorted FeO6 octahedra that share  a cornercorner with one Fe(4)O6 octahedra,  a cornercorner with one Fe(5)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and  a faceface with one Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-59°. In the fourth Fe site, Fe(4) is bonded to two equivalent O(10), two equivalent O(5), and two equivalent O(7) atoms to form FeO6 octahedra that share corners with two equivalent Fe(3)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and faces with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 49°. In the fifth Fe site, Fe(5) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with two equivalent Fe(2)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and faces with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 58-59°. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(2), one O(4), one O(5), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(2)O6 octahedra,  a cornercorner with one Fe(4)O6 octahedra,  a cornercorner with one Fe(5)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, and corners with two equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 32-47°. In the second P site, P(2) is bonded to one O(10), one O(3), one O(6), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(2)O6 octahedra,  a cornercorner with one Fe(4)O6 octahedra,  a cornercorner with one Fe(5)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, and corners with two equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 29-46°. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Fe(1), one Fe(2), one Fe(3), and one Fe(5) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(5), and one P(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Fe(2), one Fe(3), and one P(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Fe(2), one Fe(3), and one P(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(4), and one P(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(5), and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Fe(1), one Fe(3), and one Fe(4) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one Fe(3) and one P(2) atom. In the ninth O site, O(9) is bonded in a bent 150 degrees geometry to one Fe(3) and one P(1) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(4), and one P(2) atom.
Fe7(PO5)4 crystallizes in the triclinic P-1 space group. There are five inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(10), one O(2), one O(5), one O(6), and one O(7) atom to form FeO6 octahedra that share  a cornercorner with one Fe(2)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra,  a faceface with one Fe(4)O6 octahedra, and  a faceface with one Fe(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-54°. The Fe(1)-O(1) bond length is 2.01 Å. The Fe(1)-O(10) bond length is 2.11 Å. The Fe(1)-O(2) bond length is 2.07 Å. The Fe(1)-O(5) bond length is 2.10 Å. The Fe(1)-O(6) bond length is 2.02 Å. The Fe(1)-O(7) bond length is 1.98 Å. In the second Fe site, Fe(2) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form FeO6 octahedra that share corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Fe(5)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and faces with two equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 53-58°. Both Fe(2)-O(1) bond lengths are 2.05 Å. Both Fe(2)-O(3) bond lengths are 2.03 Å. Both Fe(2)-O(4) bond lengths are 2.03 Å. In the third Fe site, Fe(3) is bonded to one O(1), one O(3), one O(4), one O(7), one O(8), and one O(9) atom to form distorted FeO6 octahedra that share  a cornercorner with one Fe(4)O6 octahedra,  a cornercorner with one Fe(5)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and  a faceface with one Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-59°. The Fe(3)-O(1) bond length is 2.21 Å. The Fe(3)-O(3) bond length is 2.19 Å. The Fe(3)-O(4) bond length is 2.21 Å. The Fe(3)-O(7) bond length is 1.93 Å. The Fe(3)-O(8) bond length is 1.94 Å. The Fe(3)-O(9) bond length is 1.94 Å. In the fourth Fe site, Fe(4) is bonded to two equivalent O(10), two equivalent O(5), and two equivalent O(7) atoms to form FeO6 octahedra that share corners with two equivalent Fe(3)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and faces with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 49°. Both Fe(4)-O(10) bond lengths are 2.10 Å. Both Fe(4)-O(5) bond lengths are 2.04 Å. Both Fe(4)-O(7) bond lengths are 1.96 Å. In the fifth Fe site, Fe(5) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with two equivalent Fe(2)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and faces with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 58-59°. Both Fe(5)-O(1) bond lengths are 2.19 Å. Both Fe(5)-O(2) bond lengths are 2.11 Å. Both Fe(5)-O(6) bond lengths are 2.12 Å. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(2), one O(4), one O(5), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(2)O6 octahedra,  a cornercorner with one Fe(4)O6 octahedra,  a cornercorner with one Fe(5)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, and corners with two equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 32-47°. The P(1)-O(2) bond length is 1.56 Å. The P(1)-O(4) bond length is 1.56 Å. The P(1)-O(5) bond length is 1.56 Å. The P(1)-O(9) bond length is 1.53 Å. In the second P site, P(2) is bonded to one O(10), one O(3), one O(6), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Fe(2)O6 octahedra,  a cornercorner with one Fe(4)O6 octahedra,  a cornercorner with one Fe(5)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, and corners with two equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 29-46°. The P(2)-O(10) bond length is 1.56 Å. The P(2)-O(3) bond length is 1.54 Å. The P(2)-O(6) bond length is 1.56 Å. The P(2)-O(8) bond length is 1.52 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Fe(1), one Fe(2), one Fe(3), and one Fe(5) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(5), and one P(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Fe(2), one Fe(3), and one P(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Fe(2), one Fe(3), and one P(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(4), and one P(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(5), and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Fe(1), one Fe(3), and one Fe(4) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one Fe(3) and one P(2) atom. In the ninth O site, O(9) is bonded in a bent 150 degrees geometry to one Fe(3) and one P(1) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(4), and one P(2) atom.