Fe7(OF7)2 crystallizes in the triclinic P-1 space group. There are five inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent F(1), two equivalent F(2), and two equivalent F(3) atoms to form FeF6 octahedra that share corners with four equivalent Fe(2)OF5 octahedra and edges with two equivalent Fe(3)F6 octahedra. The corner-sharing octahedral tilt angles range from 37-46°. In the second Fe site, Fe(2) is bonded to one O(1), one F(1), one F(3), one F(4), one F(5), and one F(6) atom to form FeOF5 octahedra that share corners with two equivalent Fe(1)F6 octahedra, corners with four equivalent Fe(3)F6 octahedra,  an edgeedge with one Fe(4)O2F4 octahedra, and  an edgeedge with one Fe(5)O2F4 octahedra. The corner-sharing octahedral tilt angles range from 37-50°. In the third Fe site, Fe(3) is bonded to one F(2), one F(3), one F(4), one F(5), one F(6), and one F(7) atom to form FeF6 octahedra that share corners with two equivalent Fe(4)O2F4 octahedra, corners with two equivalent Fe(5)O2F4 octahedra, corners with four equivalent Fe(2)OF5 octahedra, and  an edgeedge with one Fe(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 42-56°. In the fourth Fe site, Fe(4) is bonded to two equivalent O(1), two equivalent F(6), and two equivalent F(7) atoms to form FeO2F4 octahedra that share corners with four equivalent Fe(3)F6 octahedra, edges with two equivalent Fe(5)O2F4 octahedra, and edges with two equivalent Fe(2)OF5 octahedra. The corner-sharing octahedral tilt angles range from 49-56°. In the fifth Fe site, Fe(5) is bonded to two equivalent O(1), two equivalent F(5), and two equivalent F(7) atoms to form FeO2F4 octahedra that share corners with four equivalent Fe(3)F6 octahedra, edges with two equivalent Fe(4)O2F4 octahedra, and edges with two equivalent Fe(2)OF5 octahedra. The corner-sharing octahedral tilt angles are 49°. O(1) is bonded in a trigonal non-coplanar geometry to one Fe(2), one Fe(4), and one Fe(5) atom. There are seven inequivalent F sites. In the first F site, F(1) is bonded in a bent 150 degrees geometry to one Fe(1) and one Fe(2) atom. In the second F site, F(2) is bonded in a water-like geometry to one Fe(1) and one Fe(3) atom. In the third F site, F(3) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(2), and one Fe(3) atom. In the fourth F site, F(4) is bonded in a distorted bent 150 degrees geometry to one Fe(2) and one Fe(3) atom. In the fifth F site, F(5) is bonded in a distorted T-shaped geometry to one Fe(2), one Fe(3), and one Fe(5) atom. In the sixth F site, F(6) is bonded in a distorted trigonal planar geometry to one Fe(2), one Fe(3), and one Fe(4) atom. In the seventh F site, F(7) is bonded in a distorted T-shaped geometry to one Fe(3), one Fe(4), and one Fe(5) atom.
Fe7(OF7)2 crystallizes in the triclinic P-1 space group. There are five inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent F(1), two equivalent F(2), and two equivalent F(3) atoms to form FeF6 octahedra that share corners with four equivalent Fe(2)OF5 octahedra and edges with two equivalent Fe(3)F6 octahedra. The corner-sharing octahedral tilt angles range from 37-46°. Both Fe(1)-F(1) bond lengths are 1.96 Å. Both Fe(1)-F(2) bond lengths are 1.91 Å. Both Fe(1)-F(3) bond lengths are 2.03 Å. In the second Fe site, Fe(2) is bonded to one O(1), one F(1), one F(3), one F(4), one F(5), and one F(6) atom to form FeOF5 octahedra that share corners with two equivalent Fe(1)F6 octahedra, corners with four equivalent Fe(3)F6 octahedra,  an edgeedge with one Fe(4)O2F4 octahedra, and  an edgeedge with one Fe(5)O2F4 octahedra. The corner-sharing octahedral tilt angles range from 37-50°. The Fe(2)-O(1) bond length is 1.91 Å. The Fe(2)-F(1) bond length is 1.97 Å. The Fe(2)-F(3) bond length is 2.04 Å. The Fe(2)-F(4) bond length is 1.91 Å. The Fe(2)-F(5) bond length is 2.12 Å. The Fe(2)-F(6) bond length is 2.10 Å. In the third Fe site, Fe(3) is bonded to one F(2), one F(3), one F(4), one F(5), one F(6), and one F(7) atom to form FeF6 octahedra that share corners with two equivalent Fe(4)O2F4 octahedra, corners with two equivalent Fe(5)O2F4 octahedra, corners with four equivalent Fe(2)OF5 octahedra, and  an edgeedge with one Fe(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 42-56°. The Fe(3)-F(2) bond length is 2.02 Å. The Fe(3)-F(3) bond length is 2.38 Å. The Fe(3)-F(4) bond length is 2.07 Å. The Fe(3)-F(5) bond length is 2.16 Å. The Fe(3)-F(6) bond length is 2.14 Å. The Fe(3)-F(7) bond length is 2.05 Å. In the fourth Fe site, Fe(4) is bonded to two equivalent O(1), two equivalent F(6), and two equivalent F(7) atoms to form FeO2F4 octahedra that share corners with four equivalent Fe(3)F6 octahedra, edges with two equivalent Fe(5)O2F4 octahedra, and edges with two equivalent Fe(2)OF5 octahedra. The corner-sharing octahedral tilt angles range from 49-56°. Both Fe(4)-O(1) bond lengths are 2.04 Å. Both Fe(4)-F(6) bond lengths are 2.16 Å. Both Fe(4)-F(7) bond lengths are 2.17 Å. In the fifth Fe site, Fe(5) is bonded to two equivalent O(1), two equivalent F(5), and two equivalent F(7) atoms to form FeO2F4 octahedra that share corners with four equivalent Fe(3)F6 octahedra, edges with two equivalent Fe(4)O2F4 octahedra, and edges with two equivalent Fe(2)OF5 octahedra. The corner-sharing octahedral tilt angles are 49°. Both Fe(5)-O(1) bond lengths are 1.90 Å. Both Fe(5)-F(5) bond lengths are 2.09 Å. Both Fe(5)-F(7) bond lengths are 2.09 Å. O(1) is bonded in a trigonal non-coplanar geometry to one Fe(2), one Fe(4), and one Fe(5) atom. There are seven inequivalent F sites. In the first F site, F(1) is bonded in a bent 150 degrees geometry to one Fe(1) and one Fe(2) atom. In the second F site, F(2) is bonded in a water-like geometry to one Fe(1) and one Fe(3) atom. In the third F site, F(3) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(2), and one Fe(3) atom. In the fourth F site, F(4) is bonded in a distorted bent 150 degrees geometry to one Fe(2) and one Fe(3) atom. In the fifth F site, F(5) is bonded in a distorted T-shaped geometry to one Fe(2), one Fe(3), and one Fe(5) atom. In the sixth F site, F(6) is bonded in a distorted trigonal planar geometry to one Fe(2), one Fe(3), and one Fe(4) atom. In the seventh F site, F(7) is bonded in a distorted T-shaped geometry to one Fe(3), one Fe(4), and one Fe(5) atom.