MgFe6O11F crystallizes in the monoclinic Pm space group. Mg(1) is bonded to one O(10), one O(8), two equivalent O(11), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with two equivalent Fe(2)O5 square pyramids, corners with two equivalent Fe(4)O3F2 trigonal bipyramids, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Fe(6)O5F octahedra, edges with two equivalent Fe(1)O6 octahedra,  an edgeedge with one Fe(2)O5 square pyramid, and  an edgeedge with one Fe(4)O3F2 trigonal bipyramid. There are six inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(3), two equivalent O(6), and two equivalent O(8) atoms to form distorted FeO6 octahedra that share corners with two equivalent Fe(5)O6 octahedra, corners with four equivalent Fe(2)O5 square pyramids, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 51°. In the second Fe site, Fe(2) is bonded to one O(4), two equivalent O(1), and two equivalent O(3) atoms to form distorted FeO5 square pyramids that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra, corners with four equivalent Fe(1)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra, and edges with two equivalent Fe(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 28-60°. In the third Fe site, Fe(3) is bonded to one O(2), one O(7), two equivalent O(4), and two equivalent O(5) atoms to form FeO6 octahedra that share corners with four equivalent Fe(5)O6 octahedra, corners with two equivalent Fe(2)O5 square pyramids, corners with two equivalent Fe(4)O3F2 trigonal bipyramids, and edges with two equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles are 49°. In the fourth Fe site, Fe(4) is bonded to one O(5), two equivalent O(11), and two equivalent F(1) atoms to form distorted FeO3F2 trigonal bipyramids that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra, corners with four equivalent Fe(6)O5F octahedra,  an edgeedge with one Mg(1)O6 octahedra, and edges with two equivalent Fe(4)O3F2 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 29-63°. In the fifth Fe site, Fe(5) is bonded to one O(6), one O(9), two equivalent O(2), and two equivalent O(7) atoms to form FeO6 octahedra that share corners with two equivalent Fe(6)O5F octahedra, corners with two equivalent Fe(1)O6 octahedra, corners with four equivalent Fe(3)O6 octahedra, and edges with two equivalent Fe(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-51°. In the sixth Fe site, Fe(6) is bonded to one O(11), two equivalent O(10), two equivalent O(9), and one F(1) atom to form FeO5F octahedra that share corners with two equivalent Fe(5)O6 octahedra, corners with four equivalent Fe(4)O3F2 trigonal bipyramids, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Fe(6)O5F octahedra. The corner-sharing octahedral tilt angles are 50°. There are eleven inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Fe(1) and two equivalent Fe(2) atoms. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Fe(3) and two equivalent Fe(5) atoms. In the third O site, O(3) is bonded in a 5-coordinate geometry to two equivalent Mg(1), one Fe(1), and two equivalent Fe(2) atoms. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Fe(2) and two equivalent Fe(3) atoms. In the fifth O site, O(5) is bonded in a distorted T-shaped geometry to one Fe(4) and two equivalent Fe(3) atoms. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Fe(5) and two equivalent Fe(1) atoms. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Fe(3) and two equivalent Fe(5) atoms. In the eighth O site, O(8) is bonded in a trigonal non-coplanar geometry to one Mg(1) and two equivalent Fe(1) atoms. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Fe(5) and two equivalent Fe(6) atoms. In the tenth O site, O(10) is bonded in a trigonal non-coplanar geometry to one Mg(1) and two equivalent Fe(6) atoms. In the eleventh O site, O(11) is bonded to two equivalent Mg(1), one Fe(6), and two equivalent Fe(4) atoms to form distorted edge-sharing OMg2Fe3 trigonal bipyramids. F(1) is bonded in a distorted T-shaped geometry to one Fe(6) and two equivalent Fe(4) atoms.
MgFe6O11F crystallizes in the monoclinic Pm space group. Mg(1) is bonded to one O(10), one O(8), two equivalent O(11), and two equivalent O(3) atoms to form MgO6 octahedra that share corners with two equivalent Fe(2)O5 square pyramids, corners with two equivalent Fe(4)O3F2 trigonal bipyramids, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Fe(6)O5F octahedra, edges with two equivalent Fe(1)O6 octahedra,  an edgeedge with one Fe(2)O5 square pyramid, and  an edgeedge with one Fe(4)O3F2 trigonal bipyramid. The Mg(1)-O(10) bond length is 2.00 Å. The Mg(1)-O(8) bond length is 1.98 Å. Both Mg(1)-O(11) bond lengths are 2.23 Å. Both Mg(1)-O(3) bond lengths are 2.08 Å. There are six inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(3), two equivalent O(6), and two equivalent O(8) atoms to form distorted FeO6 octahedra that share corners with two equivalent Fe(5)O6 octahedra, corners with four equivalent Fe(2)O5 square pyramids, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 51°. The Fe(1)-O(1) bond length is 1.96 Å. The Fe(1)-O(3) bond length is 2.46 Å. Both Fe(1)-O(6) bond lengths are 1.93 Å. Both Fe(1)-O(8) bond lengths are 1.94 Å. In the second Fe site, Fe(2) is bonded to one O(4), two equivalent O(1), and two equivalent O(3) atoms to form distorted FeO5 square pyramids that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra, corners with four equivalent Fe(1)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra, and edges with two equivalent Fe(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 28-60°. The Fe(2)-O(4) bond length is 1.91 Å. Both Fe(2)-O(1) bond lengths are 1.92 Å. Both Fe(2)-O(3) bond lengths are 2.09 Å. In the third Fe site, Fe(3) is bonded to one O(2), one O(7), two equivalent O(4), and two equivalent O(5) atoms to form FeO6 octahedra that share corners with four equivalent Fe(5)O6 octahedra, corners with two equivalent Fe(2)O5 square pyramids, corners with two equivalent Fe(4)O3F2 trigonal bipyramids, and edges with two equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles are 49°. The Fe(3)-O(2) bond length is 2.14 Å. The Fe(3)-O(7) bond length is 2.16 Å. Both Fe(3)-O(4) bond lengths are 1.94 Å. Both Fe(3)-O(5) bond lengths are 2.00 Å. In the fourth Fe site, Fe(4) is bonded to one O(5), two equivalent O(11), and two equivalent F(1) atoms to form distorted FeO3F2 trigonal bipyramids that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra, corners with four equivalent Fe(6)O5F octahedra,  an edgeedge with one Mg(1)O6 octahedra, and edges with two equivalent Fe(4)O3F2 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 29-63°. The Fe(4)-O(5) bond length is 1.84 Å. Both Fe(4)-O(11) bond lengths are 2.00 Å. Both Fe(4)-F(1) bond lengths are 2.03 Å. In the fifth Fe site, Fe(5) is bonded to one O(6), one O(9), two equivalent O(2), and two equivalent O(7) atoms to form FeO6 octahedra that share corners with two equivalent Fe(6)O5F octahedra, corners with two equivalent Fe(1)O6 octahedra, corners with four equivalent Fe(3)O6 octahedra, and edges with two equivalent Fe(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-51°. The Fe(5)-O(6) bond length is 2.07 Å. The Fe(5)-O(9) bond length is 2.10 Å. Both Fe(5)-O(2) bond lengths are 1.94 Å. Both Fe(5)-O(7) bond lengths are 1.94 Å. In the sixth Fe site, Fe(6) is bonded to one O(11), two equivalent O(10), two equivalent O(9), and one F(1) atom to form FeO5F octahedra that share corners with two equivalent Fe(5)O6 octahedra, corners with four equivalent Fe(4)O3F2 trigonal bipyramids, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Fe(6)O5F octahedra. The corner-sharing octahedral tilt angles are 50°. The Fe(6)-O(11) bond length is 2.23 Å. Both Fe(6)-O(10) bond lengths are 1.92 Å. Both Fe(6)-O(9) bond lengths are 1.92 Å. The Fe(6)-F(1) bond length is 2.17 Å. There are eleven inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Fe(1) and two equivalent Fe(2) atoms. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Fe(3) and two equivalent Fe(5) atoms. In the third O site, O(3) is bonded in a 5-coordinate geometry to two equivalent Mg(1), one Fe(1), and two equivalent Fe(2) atoms. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Fe(2) and two equivalent Fe(3) atoms. In the fifth O site, O(5) is bonded in a distorted T-shaped geometry to one Fe(4) and two equivalent Fe(3) atoms. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Fe(5) and two equivalent Fe(1) atoms. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Fe(3) and two equivalent Fe(5) atoms. In the eighth O site, O(8) is bonded in a trigonal non-coplanar geometry to one Mg(1) and two equivalent Fe(1) atoms. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Fe(5) and two equivalent Fe(6) atoms. In the tenth O site, O(10) is bonded in a trigonal non-coplanar geometry to one Mg(1) and two equivalent Fe(6) atoms. In the eleventh O site, O(11) is bonded to two equivalent Mg(1), one Fe(6), and two equivalent Fe(4) atoms to form distorted edge-sharing OMg2Fe3 trigonal bipyramids. F(1) is bonded in a distorted T-shaped geometry to one Fe(6) and two equivalent Fe(4) atoms.