MgFe6(OF)6 crystallizes in the monoclinic Pm space group. Mg(1) is bonded to one O(2), two equivalent O(3), one F(6), and two equivalent F(4) atoms to form MgO3F3 octahedra that share corners with four equivalent Fe(6)O3F3 octahedra, corners with two equivalent Fe(1)O4F square pyramids, edges with two equivalent Mg(1)O3F3 octahedra, edges with two equivalent Fe(3)O3F3 octahedra, and faces with two equivalent Fe(6)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 40-43°. There are six inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(2), two equivalent O(6), and one F(2) atom to form distorted FeO4F square pyramids that share corners with two equivalent Mg(1)O3F3 octahedra, corners with two equivalent Fe(6)O3F3 octahedra, corners with four equivalent Fe(4)O3F3 octahedra, and edges with two equivalent Fe(1)O4F square pyramids. The corner-sharing octahedral tilt angles range from 45-73°. In the second Fe site, Fe(2) is bonded to one O(4), one O(5), two equivalent F(1), and two equivalent F(5) atoms to form FeO2F4 octahedra that share corners with four equivalent Fe(4)O3F3 octahedra and edges with two equivalent Fe(2)O2F4 octahedra. The corner-sharing octahedral tilt angles range from 50-54°. In the third Fe site, Fe(3) is bonded to one O(3), two equivalent O(1), one F(3), and two equivalent F(6) atoms to form distorted FeO3F3 octahedra that share corners with four equivalent Fe(6)O3F3 octahedra, edges with two equivalent Mg(1)O3F3 octahedra, and edges with two equivalent Fe(3)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 40-59°. In the fourth Fe site, Fe(4) is bonded to one O(6), two equivalent O(5), one F(1), and two equivalent F(2) atoms to form distorted FeO3F3 octahedra that share corners with four equivalent Fe(2)O2F4 octahedra, corners with four equivalent Fe(1)O4F square pyramids, and edges with two equivalent Fe(4)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 50-54°. In the fifth Fe site, Fe(5) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(4), and two equivalent F(3) atoms. In the sixth Fe site, Fe(6) is bonded to one O(2), two equivalent O(3), one F(6), and two equivalent F(4) atoms to form distorted FeO3F3 octahedra that share corners with four equivalent Mg(1)O3F3 octahedra, corners with four equivalent Fe(3)O3F3 octahedra, corners with two equivalent Fe(1)O4F square pyramids, edges with two equivalent Fe(6)O3F3 octahedra, and faces with two equivalent Mg(1)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 40-59°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Fe(5) and two equivalent Fe(3) atoms. In the second O site, O(2) is bonded to one Mg(1), one Fe(6), and two equivalent Fe(1) atoms to form distorted OMgFe3 tetrahedra that share corners with two equivalent O(2)MgFe3 tetrahedra and edges with two equivalent O(3)Mg2Fe3 square pyramids. In the third O site, O(3) is bonded to two equivalent Mg(1), one Fe(3), and two equivalent Fe(6) atoms to form distorted OMg2Fe3 square pyramids that share edges with two equivalent O(3)Mg2Fe3 square pyramids and edges with two equivalent O(2)MgFe3 tetrahedra. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Fe(2) and two equivalent Fe(5) atoms. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Fe(2) and two equivalent Fe(4) atoms. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Fe(4) and two equivalent Fe(1) atoms. There are six inequivalent F sites. In the first F site, F(1) is bonded in a distorted trigonal planar geometry to one Fe(4) and two equivalent Fe(2) atoms. In the second F site, F(2) is bonded in a distorted T-shaped geometry to one Fe(1) and two equivalent Fe(4) atoms. In the third F site, F(3) is bonded in a distorted T-shaped geometry to one Fe(3) and two equivalent Fe(5) atoms. In the fourth F site, F(4) is bonded in a 4-coordinate geometry to two equivalent Mg(1) and two equivalent Fe(6) atoms. In the fifth F site, F(5) is bonded in a distorted water-like geometry to two equivalent Fe(2) atoms. In the sixth F site, F(6) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Fe(6), and two equivalent Fe(3) atoms.
MgFe6(OF)6 crystallizes in the monoclinic Pm space group. Mg(1) is bonded to one O(2), two equivalent O(3), one F(6), and two equivalent F(4) atoms to form MgO3F3 octahedra that share corners with four equivalent Fe(6)O3F3 octahedra, corners with two equivalent Fe(1)O4F square pyramids, edges with two equivalent Mg(1)O3F3 octahedra, edges with two equivalent Fe(3)O3F3 octahedra, and faces with two equivalent Fe(6)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 40-43°. The Mg(1)-O(2) bond length is 2.04 Å. Both Mg(1)-O(3) bond lengths are 2.08 Å. The Mg(1)-F(6) bond length is 1.96 Å. Both Mg(1)-F(4) bond lengths are 2.10 Å. There are six inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(2), two equivalent O(6), and one F(2) atom to form distorted FeO4F square pyramids that share corners with two equivalent Mg(1)O3F3 octahedra, corners with two equivalent Fe(6)O3F3 octahedra, corners with four equivalent Fe(4)O3F3 octahedra, and edges with two equivalent Fe(1)O4F square pyramids. The corner-sharing octahedral tilt angles range from 45-73°. Both Fe(1)-O(2) bond lengths are 2.02 Å. Both Fe(1)-O(6) bond lengths are 2.00 Å. The Fe(1)-F(2) bond length is 2.04 Å. In the second Fe site, Fe(2) is bonded to one O(4), one O(5), two equivalent F(1), and two equivalent F(5) atoms to form FeO2F4 octahedra that share corners with four equivalent Fe(4)O3F3 octahedra and edges with two equivalent Fe(2)O2F4 octahedra. The corner-sharing octahedral tilt angles range from 50-54°. The Fe(2)-O(4) bond length is 1.90 Å. The Fe(2)-O(5) bond length is 2.02 Å. Both Fe(2)-F(1) bond lengths are 2.08 Å. Both Fe(2)-F(5) bond lengths are 2.01 Å. In the third Fe site, Fe(3) is bonded to one O(3), two equivalent O(1), one F(3), and two equivalent F(6) atoms to form distorted FeO3F3 octahedra that share corners with four equivalent Fe(6)O3F3 octahedra, edges with two equivalent Mg(1)O3F3 octahedra, and edges with two equivalent Fe(3)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 40-59°. The Fe(3)-O(3) bond length is 2.13 Å. Both Fe(3)-O(1) bond lengths are 1.99 Å. The Fe(3)-F(3) bond length is 2.17 Å. Both Fe(3)-F(6) bond lengths are 2.43 Å. In the fourth Fe site, Fe(4) is bonded to one O(6), two equivalent O(5), one F(1), and two equivalent F(2) atoms to form distorted FeO3F3 octahedra that share corners with four equivalent Fe(2)O2F4 octahedra, corners with four equivalent Fe(1)O4F square pyramids, and edges with two equivalent Fe(4)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 50-54°. The Fe(4)-O(6) bond length is 1.93 Å. Both Fe(4)-O(5) bond lengths are 1.92 Å. The Fe(4)-F(1) bond length is 2.39 Å. Both Fe(4)-F(2) bond lengths are 2.18 Å. In the fifth Fe site, Fe(5) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(4), and two equivalent F(3) atoms. The Fe(5)-O(1) bond length is 1.83 Å. Both Fe(5)-O(4) bond lengths are 1.99 Å. Both Fe(5)-F(3) bond lengths are 2.12 Å. In the sixth Fe site, Fe(6) is bonded to one O(2), two equivalent O(3), one F(6), and two equivalent F(4) atoms to form distorted FeO3F3 octahedra that share corners with four equivalent Mg(1)O3F3 octahedra, corners with four equivalent Fe(3)O3F3 octahedra, corners with two equivalent Fe(1)O4F square pyramids, edges with two equivalent Fe(6)O3F3 octahedra, and faces with two equivalent Mg(1)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 40-59°. The Fe(6)-O(2) bond length is 2.15 Å. Both Fe(6)-O(3) bond lengths are 2.09 Å. The Fe(6)-F(6) bond length is 2.11 Å. Both Fe(6)-F(4) bond lengths are 2.30 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Fe(5) and two equivalent Fe(3) atoms. In the second O site, O(2) is bonded to one Mg(1), one Fe(6), and two equivalent Fe(1) atoms to form distorted OMgFe3 tetrahedra that share corners with two equivalent O(2)MgFe3 tetrahedra and edges with two equivalent O(3)Mg2Fe3 square pyramids. In the third O site, O(3) is bonded to two equivalent Mg(1), one Fe(3), and two equivalent Fe(6) atoms to form distorted OMg2Fe3 square pyramids that share edges with two equivalent O(3)Mg2Fe3 square pyramids and edges with two equivalent O(2)MgFe3 tetrahedra. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Fe(2) and two equivalent Fe(5) atoms. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Fe(2) and two equivalent Fe(4) atoms. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Fe(4) and two equivalent Fe(1) atoms. There are six inequivalent F sites. In the first F site, F(1) is bonded in a distorted trigonal planar geometry to one Fe(4) and two equivalent Fe(2) atoms. In the second F site, F(2) is bonded in a distorted T-shaped geometry to one Fe(1) and two equivalent Fe(4) atoms. In the third F site, F(3) is bonded in a distorted T-shaped geometry to one Fe(3) and two equivalent Fe(5) atoms. In the fourth F site, F(4) is bonded in a 4-coordinate geometry to two equivalent Mg(1) and two equivalent Fe(6) atoms. In the fifth F site, F(5) is bonded in a distorted water-like geometry to two equivalent Fe(2) atoms. In the sixth F site, F(6) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Fe(6), and two equivalent Fe(3) atoms.