MgFe6(O5F)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(10), one O(3), one O(5), one O(9), one F(1), and one F(2) atom to form MgO4F2 octahedra that share  a cornercorner with one Fe(1)O5F octahedra,  a cornercorner with one Fe(4)O5F octahedra, corners with two equivalent Fe(5)O4F2 octahedra,  a cornercorner with one Fe(2)O5 square pyramid,  a cornercorner with one Fe(3)O5 square pyramid,  a cornercorner with one Fe(6)O5 square pyramid,  an edgeedge with one Fe(6)O5 square pyramid,  a faceface with one Fe(1)O5F octahedra, and  a faceface with one Fe(4)O5F octahedra. The corner-sharing octahedral tilt angles range from 42-51°. There are six inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(10), one O(4), one O(5), one O(9), and one F(2) atom to form distorted FeO5F octahedra that share  a cornercorner with one Mg(1)O4F2 octahedra, corners with two equivalent Fe(2)O5 square pyramids, corners with two equivalent Fe(3)O5 square pyramids, corners with two equivalent Fe(6)O5 square pyramids,  an edgeedge with one Fe(5)O4F2 octahedra,  an edgeedge with one Fe(4)O5F octahedra, and  a faceface with one Mg(1)O4F2 octahedra. The corner-sharing octahedral tilt angles are 51°. In the second Fe site, Fe(2) is bonded to one O(1), one O(3), one O(4), one O(6), and one O(7) atom to form distorted FeO5 square pyramids that share  a cornercorner with one Mg(1)O4F2 octahedra, corners with two equivalent Fe(5)O4F2 octahedra, corners with two equivalent Fe(1)O5F octahedra, corners with two equivalent Fe(4)O5F octahedra,  an edgeedge with one Fe(3)O5 square pyramid, and  an edgeedge with one Fe(6)O5 square pyramid. The corner-sharing octahedral tilt angles range from 46-71°. In the third Fe site, Fe(3) is bonded to one O(2), one O(4), one O(5), one O(6), and one O(8) atom to form distorted FeO5 square pyramids that share  a cornercorner with one Mg(1)O4F2 octahedra, corners with two equivalent Fe(5)O4F2 octahedra, corners with two equivalent Fe(1)O5F octahedra, corners with two equivalent Fe(4)O5F octahedra,  an edgeedge with one Fe(2)O5 square pyramid, and  an edgeedge with one Fe(6)O5 square pyramid. The corner-sharing octahedral tilt angles range from 47-70°. In the fourth Fe site, Fe(4) is bonded to one O(10), one O(3), one O(6), one O(8), one O(9), and one F(1) atom to form distorted FeO5F octahedra that share  a cornercorner with one Mg(1)O4F2 octahedra, corners with two equivalent Fe(2)O5 square pyramids, corners with two equivalent Fe(3)O5 square pyramids, corners with two equivalent Fe(6)O5 square pyramids,  an edgeedge with one Fe(5)O4F2 octahedra,  an edgeedge with one Fe(1)O5F octahedra, and  a faceface with one Mg(1)O4F2 octahedra. The corner-sharing octahedral tilt angles are 48°. In the fifth Fe site, Fe(5) is bonded to one O(1), one O(2), one O(7), one O(8), one F(1), and one F(2) atom to form FeO4F2 octahedra that share corners with two equivalent Mg(1)O4F2 octahedra, corners with two equivalent Fe(2)O5 square pyramids, corners with two equivalent Fe(3)O5 square pyramids, corners with two equivalent Fe(6)O5 square pyramids,  an edgeedge with one Fe(1)O5F octahedra, and  an edgeedge with one Fe(4)O5F octahedra. The corner-sharing octahedral tilt angles range from 42-45°. In the sixth Fe site, Fe(6) is bonded to one O(10), one O(2), one O(3), one O(5), and one O(7) atom to form distorted FeO5 square pyramids that share  a cornercorner with one Mg(1)O4F2 octahedra, corners with two equivalent Fe(5)O4F2 octahedra, corners with two equivalent Fe(1)O5F octahedra, corners with two equivalent Fe(4)O5F octahedra,  an edgeedge with one Mg(1)O4F2 octahedra,  an edgeedge with one Fe(2)O5 square pyramid, and  an edgeedge with one Fe(3)O5 square pyramid. The corner-sharing octahedral tilt angles range from 32-79°. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Fe(1), one Fe(2), and one Fe(5) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Fe(3), one Fe(5), and one Fe(6) atom. In the third O site, O(3) is bonded to one Mg(1), one Fe(2), one Fe(4), and one Fe(6) atom to form distorted corner-sharing OMgFe3 trigonal pyramids. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Fe(1), one Fe(2), and one Fe(3) atom. In the fifth O site, O(5) is bonded to one Mg(1), one Fe(1), one Fe(3), and one Fe(6) atom to form distorted corner-sharing OMgFe3 trigonal pyramids. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Fe(2), one Fe(3), and one Fe(4) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Fe(2), one Fe(5), and one Fe(6) atom. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Fe(3), one Fe(4), and one Fe(5) atom. In the ninth O site, O(9) is bonded in a distorted T-shaped geometry to one Mg(1), one Fe(1), and one Fe(4) atom. In the tenth O site, O(10) is bonded in a distorted see-saw-like geometry to one Mg(1), one Fe(1), one Fe(4), and one Fe(6) atom. There are two inequivalent F sites. In the first F site, F(1) is bonded in a T-shaped geometry to one Mg(1), one Fe(4), and one Fe(5) atom. In the second F site, F(2) is bonded in a distorted T-shaped geometry to one Mg(1), one Fe(1), and one Fe(5) atom.
MgFe6(O5F)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(10), one O(3), one O(5), one O(9), one F(1), and one F(2) atom to form MgO4F2 octahedra that share  a cornercorner with one Fe(1)O5F octahedra,  a cornercorner with one Fe(4)O5F octahedra, corners with two equivalent Fe(5)O4F2 octahedra,  a cornercorner with one Fe(2)O5 square pyramid,  a cornercorner with one Fe(3)O5 square pyramid,  a cornercorner with one Fe(6)O5 square pyramid,  an edgeedge with one Fe(6)O5 square pyramid,  a faceface with one Fe(1)O5F octahedra, and  a faceface with one Fe(4)O5F octahedra. The corner-sharing octahedral tilt angles range from 42-51°. The Mg(1)-O(10) bond length is 2.06 Å. The Mg(1)-O(3) bond length is 2.02 Å. The Mg(1)-O(5) bond length is 2.06 Å. The Mg(1)-O(9) bond length is 1.99 Å. The Mg(1)-F(1) bond length is 2.10 Å. The Mg(1)-F(2) bond length is 2.08 Å. There are six inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(10), one O(4), one O(5), one O(9), and one F(2) atom to form distorted FeO5F octahedra that share  a cornercorner with one Mg(1)O4F2 octahedra, corners with two equivalent Fe(2)O5 square pyramids, corners with two equivalent Fe(3)O5 square pyramids, corners with two equivalent Fe(6)O5 square pyramids,  an edgeedge with one Fe(5)O4F2 octahedra,  an edgeedge with one Fe(4)O5F octahedra, and  a faceface with one Mg(1)O4F2 octahedra. The corner-sharing octahedral tilt angles are 51°. The Fe(1)-O(1) bond length is 1.94 Å. The Fe(1)-O(10) bond length is 1.94 Å. The Fe(1)-O(4) bond length is 1.94 Å. The Fe(1)-O(5) bond length is 2.19 Å. The Fe(1)-O(9) bond length is 1.99 Å. The Fe(1)-F(2) bond length is 2.22 Å. In the second Fe site, Fe(2) is bonded to one O(1), one O(3), one O(4), one O(6), and one O(7) atom to form distorted FeO5 square pyramids that share  a cornercorner with one Mg(1)O4F2 octahedra, corners with two equivalent Fe(5)O4F2 octahedra, corners with two equivalent Fe(1)O5F octahedra, corners with two equivalent Fe(4)O5F octahedra,  an edgeedge with one Fe(3)O5 square pyramid, and  an edgeedge with one Fe(6)O5 square pyramid. The corner-sharing octahedral tilt angles range from 46-71°. The Fe(2)-O(1) bond length is 1.94 Å. The Fe(2)-O(3) bond length is 2.03 Å. The Fe(2)-O(4) bond length is 1.98 Å. The Fe(2)-O(6) bond length is 1.95 Å. The Fe(2)-O(7) bond length is 1.98 Å. In the third Fe site, Fe(3) is bonded to one O(2), one O(4), one O(5), one O(6), and one O(8) atom to form distorted FeO5 square pyramids that share  a cornercorner with one Mg(1)O4F2 octahedra, corners with two equivalent Fe(5)O4F2 octahedra, corners with two equivalent Fe(1)O5F octahedra, corners with two equivalent Fe(4)O5F octahedra,  an edgeedge with one Fe(2)O5 square pyramid, and  an edgeedge with one Fe(6)O5 square pyramid. The corner-sharing octahedral tilt angles range from 47-70°. The Fe(3)-O(2) bond length is 1.97 Å. The Fe(3)-O(4) bond length is 1.93 Å. The Fe(3)-O(5) bond length is 1.99 Å. The Fe(3)-O(6) bond length is 1.96 Å. The Fe(3)-O(8) bond length is 1.94 Å. In the fourth Fe site, Fe(4) is bonded to one O(10), one O(3), one O(6), one O(8), one O(9), and one F(1) atom to form distorted FeO5F octahedra that share  a cornercorner with one Mg(1)O4F2 octahedra, corners with two equivalent Fe(2)O5 square pyramids, corners with two equivalent Fe(3)O5 square pyramids, corners with two equivalent Fe(6)O5 square pyramids,  an edgeedge with one Fe(5)O4F2 octahedra,  an edgeedge with one Fe(1)O5F octahedra, and  a faceface with one Mg(1)O4F2 octahedra. The corner-sharing octahedral tilt angles are 48°. The Fe(4)-O(10) bond length is 2.18 Å. The Fe(4)-O(3) bond length is 2.15 Å. The Fe(4)-O(6) bond length is 1.94 Å. The Fe(4)-O(8) bond length is 1.94 Å. The Fe(4)-O(9) bond length is 1.88 Å. The Fe(4)-F(1) bond length is 2.15 Å. In the fifth Fe site, Fe(5) is bonded to one O(1), one O(2), one O(7), one O(8), one F(1), and one F(2) atom to form FeO4F2 octahedra that share corners with two equivalent Mg(1)O4F2 octahedra, corners with two equivalent Fe(2)O5 square pyramids, corners with two equivalent Fe(3)O5 square pyramids, corners with two equivalent Fe(6)O5 square pyramids,  an edgeedge with one Fe(1)O5F octahedra, and  an edgeedge with one Fe(4)O5F octahedra. The corner-sharing octahedral tilt angles range from 42-45°. The Fe(5)-O(1) bond length is 1.96 Å. The Fe(5)-O(2) bond length is 2.03 Å. The Fe(5)-O(7) bond length is 2.00 Å. The Fe(5)-O(8) bond length is 1.97 Å. The Fe(5)-F(1) bond length is 2.07 Å. The Fe(5)-F(2) bond length is 2.03 Å. In the sixth Fe site, Fe(6) is bonded to one O(10), one O(2), one O(3), one O(5), and one O(7) atom to form distorted FeO5 square pyramids that share  a cornercorner with one Mg(1)O4F2 octahedra, corners with two equivalent Fe(5)O4F2 octahedra, corners with two equivalent Fe(1)O5F octahedra, corners with two equivalent Fe(4)O5F octahedra,  an edgeedge with one Mg(1)O4F2 octahedra,  an edgeedge with one Fe(2)O5 square pyramid, and  an edgeedge with one Fe(3)O5 square pyramid. The corner-sharing octahedral tilt angles range from 32-79°. The Fe(6)-O(10) bond length is 2.03 Å. The Fe(6)-O(2) bond length is 1.94 Å. The Fe(6)-O(3) bond length is 1.95 Å. The Fe(6)-O(5) bond length is 1.97 Å. The Fe(6)-O(7) bond length is 1.95 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Fe(1), one Fe(2), and one Fe(5) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Fe(3), one Fe(5), and one Fe(6) atom. In the third O site, O(3) is bonded to one Mg(1), one Fe(2), one Fe(4), and one Fe(6) atom to form distorted corner-sharing OMgFe3 trigonal pyramids. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Fe(1), one Fe(2), and one Fe(3) atom. In the fifth O site, O(5) is bonded to one Mg(1), one Fe(1), one Fe(3), and one Fe(6) atom to form distorted corner-sharing OMgFe3 trigonal pyramids. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Fe(2), one Fe(3), and one Fe(4) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Fe(2), one Fe(5), and one Fe(6) atom. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Fe(3), one Fe(4), and one Fe(5) atom. In the ninth O site, O(9) is bonded in a distorted T-shaped geometry to one Mg(1), one Fe(1), and one Fe(4) atom. In the tenth O site, O(10) is bonded in a distorted see-saw-like geometry to one Mg(1), one Fe(1), one Fe(4), and one Fe(6) atom. There are two inequivalent F sites. In the first F site, F(1) is bonded in a T-shaped geometry to one Mg(1), one Fe(4), and one Fe(5) atom. In the second F site, F(2) is bonded in a distorted T-shaped geometry to one Mg(1), one Fe(1), and one Fe(5) atom.