Fe4OF8 crystallizes in the triclinic P1 space group. There are eight inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one F(1), one F(15), one F(3), one F(6), and one F(9) atom to form distorted FeOF5 octahedra that share corners with three equivalent Fe(7)F6 octahedra and  a faceface with one Fe(3)OF5 octahedra. The corner-sharing octahedral tilt angles range from 34-43°. In the second Fe site, Fe(2) is bonded to one O(2), one F(10), one F(11), one F(16), one F(2), and one F(7) atom to form distorted FeOF5 octahedra that share corners with three equivalent Fe(7)F6 octahedra and  a faceface with one Fe(4)OF5 octahedra. The corner-sharing octahedral tilt angles range from 39-41°. In the third Fe site, Fe(3) is bonded to one O(1), one F(13), one F(14), one F(3), one F(8), and one F(9) atom to form distorted FeOF5 octahedra that share corners with three equivalent Fe(8)F6 octahedra and  a faceface with one Fe(1)OF5 octahedra. The corner-sharing octahedral tilt angles range from 39-41°. In the fourth Fe site, Fe(4) is bonded to one O(2), one F(12), one F(2), one F(4), one F(5), and one F(7) atom to form distorted FeOF5 octahedra that share corners with three equivalent Fe(8)F6 octahedra and  a faceface with one Fe(2)OF5 octahedra. The corner-sharing octahedral tilt angles range from 36-41°. In the fifth Fe site, Fe(5) is bonded in a 6-coordinate geometry to one O(1), one F(13), one F(14), one F(3), one F(8), and one F(9) atom. In the sixth Fe site, Fe(6) is bonded in a 6-coordinate geometry to one O(2), one F(10), one F(11), one F(16), one F(2), and one F(7) atom. In the seventh Fe site, Fe(7) is bonded to one F(1), one F(10), one F(11), one F(15), one F(16), and one F(6) atom to form distorted corner-sharing FeF6 octahedra. The corner-sharing octahedral tilt angles range from 34-43°. In the eighth Fe site, Fe(8) is bonded to one F(12), one F(13), one F(14), one F(4), one F(5), and one F(8) atom to form distorted corner-sharing FeF6 octahedra. The corner-sharing octahedral tilt angles range from 36-41°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Fe(1), one Fe(3), and one Fe(5) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Fe(2), one Fe(4), and one Fe(6) atom. There are sixteen 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(7) atom. In the second F site, F(2) is bonded in a distorted T-shaped geometry to one Fe(2), one Fe(4), and one Fe(6) atom. In the third F site, F(3) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(3), and one Fe(5) atom. In the fourth F site, F(4) is bonded in a bent 150 degrees geometry to one Fe(4) and one Fe(8) atom. In the fifth F site, F(5) is bonded in a bent 150 degrees geometry to one Fe(4) and one Fe(8) atom. In the sixth F site, F(6) is bonded in a bent 150 degrees geometry to one Fe(1) and one Fe(7) atom. In the seventh F site, F(7) is bonded in a 3-coordinate geometry to one Fe(2), one Fe(4), and one Fe(6) atom. In the eighth F site, F(8) is bonded in a T-shaped geometry to one Fe(3), one Fe(5), and one Fe(8) atom. In the ninth F site, F(9) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(3), and one Fe(5) atom. In the tenth F site, F(10) is bonded in a T-shaped geometry to one Fe(2), one Fe(6), and one Fe(7) atom. In the eleventh F site, F(11) is bonded in a T-shaped geometry to one Fe(2), one Fe(6), and one Fe(7) atom. In the twelfth F site, F(12) is bonded in a bent 150 degrees geometry to one Fe(4) and one Fe(8) atom. In the thirteenth F site, F(13) is bonded in a T-shaped geometry to one Fe(3), one Fe(5), and one Fe(8) atom. In the fourteenth F site, F(14) is bonded in a T-shaped geometry to one Fe(3), one Fe(5), and one Fe(8) atom. In the fifteenth F site, F(15) is bonded in a bent 150 degrees geometry to one Fe(1) and one Fe(7) atom. In the sixteenth F site, F(16) is bonded in a T-shaped geometry to one Fe(2), one Fe(6), and one Fe(7) atom.
Fe4OF8 crystallizes in the triclinic P1 space group. There are eight inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one F(1), one F(15), one F(3), one F(6), and one F(9) atom to form distorted FeOF5 octahedra that share corners with three equivalent Fe(7)F6 octahedra and  a faceface with one Fe(3)OF5 octahedra. The corner-sharing octahedral tilt angles range from 34-43°. The Fe(1)-O(1) bond length is 2.01 Å. The Fe(1)-F(1) bond length is 2.08 Å. The Fe(1)-F(15) bond length is 2.09 Å. The Fe(1)-F(3) bond length is 2.29 Å. The Fe(1)-F(6) bond length is 2.11 Å. The Fe(1)-F(9) bond length is 2.36 Å. In the second Fe site, Fe(2) is bonded to one O(2), one F(10), one F(11), one F(16), one F(2), and one F(7) atom to form distorted FeOF5 octahedra that share corners with three equivalent Fe(7)F6 octahedra and  a faceface with one Fe(4)OF5 octahedra. The corner-sharing octahedral tilt angles range from 39-41°. The Fe(2)-O(2) bond length is 2.05 Å. The Fe(2)-F(10) bond length is 2.10 Å. The Fe(2)-F(11) bond length is 2.14 Å. The Fe(2)-F(16) bond length is 2.11 Å. The Fe(2)-F(2) bond length is 2.17 Å. The Fe(2)-F(7) bond length is 2.20 Å. In the third Fe site, Fe(3) is bonded to one O(1), one F(13), one F(14), one F(3), one F(8), and one F(9) atom to form distorted FeOF5 octahedra that share corners with three equivalent Fe(8)F6 octahedra and  a faceface with one Fe(1)OF5 octahedra. The corner-sharing octahedral tilt angles range from 39-41°. The Fe(3)-O(1) bond length is 2.03 Å. The Fe(3)-F(13) bond length is 2.10 Å. The Fe(3)-F(14) bond length is 2.15 Å. The Fe(3)-F(3) bond length is 2.17 Å. The Fe(3)-F(8) bond length is 2.07 Å. The Fe(3)-F(9) bond length is 2.21 Å. In the fourth Fe site, Fe(4) is bonded to one O(2), one F(12), one F(2), one F(4), one F(5), and one F(7) atom to form distorted FeOF5 octahedra that share corners with three equivalent Fe(8)F6 octahedra and  a faceface with one Fe(2)OF5 octahedra. The corner-sharing octahedral tilt angles range from 36-41°. The Fe(4)-O(2) bond length is 2.05 Å. The Fe(4)-F(12) bond length is 2.10 Å. The Fe(4)-F(2) bond length is 2.30 Å. The Fe(4)-F(4) bond length is 2.07 Å. The Fe(4)-F(5) bond length is 2.10 Å. The Fe(4)-F(7) bond length is 2.35 Å. In the fifth Fe site, Fe(5) is bonded in a 6-coordinate geometry to one O(1), one F(13), one F(14), one F(3), one F(8), and one F(9) atom. The Fe(5)-O(1) bond length is 1.82 Å. The Fe(5)-F(13) bond length is 2.24 Å. The Fe(5)-F(14) bond length is 2.15 Å. The Fe(5)-F(3) bond length is 1.95 Å. The Fe(5)-F(8) bond length is 2.15 Å. The Fe(5)-F(9) bond length is 1.92 Å. In the sixth Fe site, Fe(6) is bonded in a 6-coordinate geometry to one O(2), one F(10), one F(11), one F(16), one F(2), and one F(7) atom. The Fe(6)-O(2) bond length is 1.82 Å. The Fe(6)-F(10) bond length is 2.15 Å. The Fe(6)-F(11) bond length is 2.14 Å. The Fe(6)-F(16) bond length is 2.22 Å. The Fe(6)-F(2) bond length is 1.95 Å. The Fe(6)-F(7) bond length is 1.92 Å. In the seventh Fe site, Fe(7) is bonded to one F(1), one F(10), one F(11), one F(15), one F(16), and one F(6) atom to form distorted corner-sharing FeF6 octahedra. The corner-sharing octahedral tilt angles range from 34-43°. The Fe(7)-F(1) bond length is 1.89 Å. The Fe(7)-F(10) bond length is 2.15 Å. The Fe(7)-F(11) bond length is 2.05 Å. The Fe(7)-F(15) bond length is 1.88 Å. The Fe(7)-F(16) bond length is 2.07 Å. The Fe(7)-F(6) bond length is 1.92 Å. In the eighth Fe site, Fe(8) is bonded to one F(12), one F(13), one F(14), one F(4), one F(5), and one F(8) atom to form distorted corner-sharing FeF6 octahedra. The corner-sharing octahedral tilt angles range from 36-41°. The Fe(8)-F(12) bond length is 1.88 Å. The Fe(8)-F(13) bond length is 2.06 Å. The Fe(8)-F(14) bond length is 2.03 Å. The Fe(8)-F(4) bond length is 1.92 Å. The Fe(8)-F(5) bond length is 1.89 Å. The Fe(8)-F(8) bond length is 2.15 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Fe(1), one Fe(3), and one Fe(5) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Fe(2), one Fe(4), and one Fe(6) atom. There are sixteen 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(7) atom. In the second F site, F(2) is bonded in a distorted T-shaped geometry to one Fe(2), one Fe(4), and one Fe(6) atom. In the third F site, F(3) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(3), and one Fe(5) atom. In the fourth F site, F(4) is bonded in a bent 150 degrees geometry to one Fe(4) and one Fe(8) atom. In the fifth F site, F(5) is bonded in a bent 150 degrees geometry to one Fe(4) and one Fe(8) atom. In the sixth F site, F(6) is bonded in a bent 150 degrees geometry to one Fe(1) and one Fe(7) atom. In the seventh F site, F(7) is bonded in a 3-coordinate geometry to one Fe(2), one Fe(4), and one Fe(6) atom. In the eighth F site, F(8) is bonded in a T-shaped geometry to one Fe(3), one Fe(5), and one Fe(8) atom. In the ninth F site, F(9) is bonded in a 3-coordinate geometry to one Fe(1), one Fe(3), and one Fe(5) atom. In the tenth F site, F(10) is bonded in a T-shaped geometry to one Fe(2), one Fe(6), and one Fe(7) atom. In the eleventh F site, F(11) is bonded in a T-shaped geometry to one Fe(2), one Fe(6), and one Fe(7) atom. In the twelfth F site, F(12) is bonded in a bent 150 degrees geometry to one Fe(4) and one Fe(8) atom. In the thirteenth F site, F(13) is bonded in a T-shaped geometry to one Fe(3), one Fe(5), and one Fe(8) atom. In the fourteenth F site, F(14) is bonded in a T-shaped geometry to one Fe(3), one Fe(5), and one Fe(8) atom. In the fifteenth F site, F(15) is bonded in a bent 150 degrees geometry to one Fe(1) and one Fe(7) atom. In the sixteenth F site, F(16) is bonded in a T-shaped geometry to one Fe(2), one Fe(6), and one Fe(7) atom.