MgFe6(O5F)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(9), two equivalent O(1), two equivalent O(7), and one F(2) atom to form MgO5F octahedra that share corners with two equivalent Fe(2)O5 square pyramids, corners with two equivalent Fe(4)O5 square pyramids, edges with two equivalent Mg(1)O5F octahedra, edges with two equivalent Fe(1)O4F2 octahedra, edges with two equivalent Fe(6)O6 octahedra,  an edgeedge with one Fe(2)O5 square pyramid, and  an edgeedge with one Fe(4)O5 square pyramid. There are six inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(2), two equivalent O(5), and two equivalent F(2) atoms to form distorted FeO4F2 octahedra that share corners with two equivalent Fe(5)O4F2 octahedra, corners with four equivalent Fe(2)O5 square pyramids, edges with two equivalent Mg(1)O5F octahedra, and edges with two equivalent Fe(1)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 54-55°. In the second Fe site, Fe(2) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form distorted FeO5 square pyramids that share corners with two equivalent Mg(1)O5F octahedra, corners with two equivalent Fe(3)O5F octahedra, corners with four equivalent Fe(1)O4F2 octahedra,  an edgeedge with one Mg(1)O5F octahedra, and edges with two equivalent Fe(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 32-62°. In the third Fe site, Fe(3) is bonded to one O(6), two equivalent O(3), two equivalent O(4), and one F(1) atom to form FeO5F octahedra that share corners with four equivalent Fe(5)O4F2 octahedra, corners with two equivalent Fe(2)O5 square pyramids, corners with two equivalent Fe(4)O5 square pyramids, and edges with two equivalent Fe(3)O5F octahedra. The corner-sharing octahedral tilt angles range from 47-51°. In the fourth Fe site, Fe(4) is bonded to one O(4), two equivalent O(10), and two equivalent O(7) atoms to form distorted FeO5 square pyramids that share corners with two equivalent Mg(1)O5F octahedra, corners with two equivalent Fe(3)O5F octahedra, corners with four equivalent Fe(6)O6 octahedra,  an edgeedge with one Mg(1)O5F octahedra, and edges with two equivalent Fe(4)O5 square pyramids. The corner-sharing octahedral tilt angles range from 28-61°. In the fifth Fe site, Fe(5) is bonded to one O(5), one O(8), two equivalent O(6), and two equivalent F(1) atoms to form FeO4F2 octahedra that share corners with two equivalent Fe(1)O4F2 octahedra, corners with two equivalent Fe(6)O6 octahedra, corners with four equivalent Fe(3)O5F octahedra, and edges with two equivalent Fe(5)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 47-55°. In the sixth Fe site, Fe(6) is bonded to one O(10), one O(7), two equivalent O(8), and two equivalent O(9) atoms to form distorted FeO6 octahedra that share corners with two equivalent Fe(5)O4F2 octahedra, corners with four equivalent Fe(4)O5 square pyramids, edges with two equivalent Mg(1)O5F octahedra, and edges with two equivalent Fe(6)O6 octahedra. The corner-sharing octahedral tilt angles are 51°. There are ten inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(1), one Fe(1), and two equivalent Fe(2) atoms to form a mixture of distorted corner and edge-sharing OMg2Fe3 trigonal bipyramids. In the second O site, O(2) is bonded in a trigonal planar geometry to one Fe(1) and two equivalent Fe(2) atoms. In the third O site, O(3) is bonded in a trigonal planar geometry to one Fe(2) and two equivalent Fe(3) atoms. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Fe(4) and two equivalent Fe(3) atoms. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Fe(5) and two equivalent Fe(1) atoms. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Fe(3) and two equivalent Fe(5) atoms. In the seventh O site, O(7) is bonded to two equivalent Mg(1), one Fe(6), and two equivalent Fe(4) atoms to form a mixture of distorted corner and edge-sharing OMg2Fe3 trigonal bipyramids. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Fe(5) and two equivalent Fe(6) atoms. In the ninth O site, O(9) is bonded in a trigonal non-coplanar geometry to one Mg(1) and two equivalent Fe(6) atoms. In the tenth O site, O(10) is bonded in a trigonal planar geometry to one Fe(6) and two equivalent Fe(4) atoms. There are two inequivalent F sites. In the first F site, F(1) is bonded in a distorted T-shaped geometry to one Fe(3) and two equivalent Fe(5) atoms. In the second F site, F(2) is bonded in a trigonal non-coplanar geometry to one Mg(1) and two equivalent Fe(1) atoms.
MgFe6(O5F)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(9), two equivalent O(1), two equivalent O(7), and one F(2) atom to form MgO5F octahedra that share corners with two equivalent Fe(2)O5 square pyramids, corners with two equivalent Fe(4)O5 square pyramids, edges with two equivalent Mg(1)O5F octahedra, edges with two equivalent Fe(1)O4F2 octahedra, edges with two equivalent Fe(6)O6 octahedra,  an edgeedge with one Fe(2)O5 square pyramid, and  an edgeedge with one Fe(4)O5 square pyramid. The Mg(1)-O(9) bond length is 2.00 Å. Both Mg(1)-O(1) bond lengths are 2.14 Å. There is one shorter (2.15 Å) and one longer (2.16 Å) Mg(1)-O(7) bond length. The Mg(1)-F(2) bond length is 1.98 Å. There are six inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(2), two equivalent O(5), and two equivalent F(2) atoms to form distorted FeO4F2 octahedra that share corners with two equivalent Fe(5)O4F2 octahedra, corners with four equivalent Fe(2)O5 square pyramids, edges with two equivalent Mg(1)O5F octahedra, and edges with two equivalent Fe(1)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 54-55°. The Fe(1)-O(1) bond length is 2.38 Å. The Fe(1)-O(2) bond length is 1.96 Å. Both Fe(1)-O(5) bond lengths are 1.91 Å. Both Fe(1)-F(2) bond lengths are 2.11 Å. In the second Fe site, Fe(2) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form distorted FeO5 square pyramids that share corners with two equivalent Mg(1)O5F octahedra, corners with two equivalent Fe(3)O5F octahedra, corners with four equivalent Fe(1)O4F2 octahedra,  an edgeedge with one Mg(1)O5F octahedra, and edges with two equivalent Fe(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 32-62°. The Fe(2)-O(3) bond length is 1.91 Å. There is one shorter (2.12 Å) and one longer (2.13 Å) Fe(2)-O(1) bond length. Both Fe(2)-O(2) bond lengths are 1.95 Å. In the third Fe site, Fe(3) is bonded to one O(6), two equivalent O(3), two equivalent O(4), and one F(1) atom to form FeO5F octahedra that share corners with four equivalent Fe(5)O4F2 octahedra, corners with two equivalent Fe(2)O5 square pyramids, corners with two equivalent Fe(4)O5 square pyramids, and edges with two equivalent Fe(3)O5F octahedra. The corner-sharing octahedral tilt angles range from 47-51°. The Fe(3)-O(6) bond length is 1.96 Å. Both Fe(3)-O(3) bond lengths are 1.94 Å. Both Fe(3)-O(4) bond lengths are 1.93 Å. The Fe(3)-F(1) bond length is 2.22 Å. In the fourth Fe site, Fe(4) is bonded to one O(4), two equivalent O(10), and two equivalent O(7) atoms to form distorted FeO5 square pyramids that share corners with two equivalent Mg(1)O5F octahedra, corners with two equivalent Fe(3)O5F octahedra, corners with four equivalent Fe(6)O6 octahedra,  an edgeedge with one Mg(1)O5F octahedra, and edges with two equivalent Fe(4)O5 square pyramids. The corner-sharing octahedral tilt angles range from 28-61°. The Fe(4)-O(4) bond length is 1.90 Å. Both Fe(4)-O(10) bond lengths are 1.93 Å. Both Fe(4)-O(7) bond lengths are 2.08 Å. In the fifth Fe site, Fe(5) is bonded to one O(5), one O(8), two equivalent O(6), and two equivalent F(1) atoms to form FeO4F2 octahedra that share corners with two equivalent Fe(1)O4F2 octahedra, corners with two equivalent Fe(6)O6 octahedra, corners with four equivalent Fe(3)O5F octahedra, and edges with two equivalent Fe(5)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 47-55°. The Fe(5)-O(5) bond length is 2.00 Å. The Fe(5)-O(8) bond length is 2.01 Å. Both Fe(5)-O(6) bond lengths are 1.91 Å. Both Fe(5)-F(1) bond lengths are 2.05 Å. In the sixth Fe site, Fe(6) is bonded to one O(10), one O(7), two equivalent O(8), and two equivalent O(9) atoms to form distorted FeO6 octahedra that share corners with two equivalent Fe(5)O4F2 octahedra, corners with four equivalent Fe(4)O5 square pyramids, edges with two equivalent Mg(1)O5F octahedra, and edges with two equivalent Fe(6)O6 octahedra. The corner-sharing octahedral tilt angles are 51°. The Fe(6)-O(10) bond length is 1.97 Å. The Fe(6)-O(7) bond length is 2.42 Å. Both Fe(6)-O(8) bond lengths are 1.95 Å. Both Fe(6)-O(9) bond lengths are 1.92 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(1), one Fe(1), and two equivalent Fe(2) atoms to form a mixture of distorted corner and edge-sharing OMg2Fe3 trigonal bipyramids. In the second O site, O(2) is bonded in a trigonal planar geometry to one Fe(1) and two equivalent Fe(2) atoms. In the third O site, O(3) is bonded in a trigonal planar geometry to one Fe(2) and two equivalent Fe(3) atoms. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Fe(4) and two equivalent Fe(3) atoms. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Fe(5) and two equivalent Fe(1) atoms. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Fe(3) and two equivalent Fe(5) atoms. In the seventh O site, O(7) is bonded to two equivalent Mg(1), one Fe(6), and two equivalent Fe(4) atoms to form a mixture of distorted corner and edge-sharing OMg2Fe3 trigonal bipyramids. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Fe(5) and two equivalent Fe(6) atoms. In the ninth O site, O(9) is bonded in a trigonal non-coplanar geometry to one Mg(1) and two equivalent Fe(6) atoms. In the tenth O site, O(10) is bonded in a trigonal planar geometry to one Fe(6) and two equivalent Fe(4) atoms. There are two inequivalent F sites. In the first F site, F(1) is bonded in a distorted T-shaped geometry to one Fe(3) and two equivalent Fe(5) atoms. In the second F site, F(2) is bonded in a trigonal non-coplanar geometry to one Mg(1) and two equivalent Fe(1) atoms.