MgFe6O7F5 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(5), one O(7), one F(1), and one F(3) atom to form MgO4F2 octahedra that share corners with two equivalent Fe(1)O4F square pyramids,  a cornercorner with one Fe(4)O4F trigonal bipyramid,  a cornercorner with one Fe(5)O4F trigonal bipyramid,  an edgeedge with one Fe(2)O3F3 octahedra,  an edgeedge with one Fe(6)O3F3 octahedra, edges with two equivalent Fe(3)O3F3 octahedra,  an edgeedge with one Fe(4)O4F trigonal bipyramid, and  an edgeedge with one Fe(5)O4F trigonal bipyramid. There are six inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(4), one O(6), one O(7), and one F(5) atom to form distorted FeO4F square pyramids that share  a cornercorner with one Fe(3)O3F3 octahedra, corners with two equivalent Mg(1)O4F2 octahedra, corners with two equivalent Fe(2)O3F3 octahedra, corners with three equivalent Fe(6)O3F3 octahedra,  an edgeedge with one Fe(4)O4F trigonal bipyramid, and  an edgeedge with one Fe(5)O4F trigonal bipyramid. The corner-sharing octahedral tilt angles range from 41-65°. In the second Fe site, Fe(2) is bonded to one O(1), one O(3), one O(6), one F(2), one F(3), and one F(4) atom to form FeO3F3 octahedra that share corners with two equivalent Fe(1)O4F square pyramids,  a cornercorner with one Fe(4)O4F trigonal bipyramid, corners with three equivalent Fe(5)O4F trigonal bipyramids,  an edgeedge with one Mg(1)O4F2 octahedra,  an edgeedge with one Fe(3)O3F3 octahedra, and  an edgeedge with one Fe(6)O3F3 octahedra. In the third Fe site, Fe(3) is bonded to one O(2), one O(4), one O(5), one F(1), one F(2), and one F(3) atom to form FeO3F3 octahedra that share  a cornercorner with one Fe(1)O4F square pyramid, corners with two equivalent Fe(4)O4F trigonal bipyramids, corners with two equivalent Fe(5)O4F trigonal bipyramids,  an edgeedge with one Fe(2)O3F3 octahedra,  an edgeedge with one Fe(6)O3F3 octahedra, and edges with two equivalent Mg(1)O4F2 octahedra. In the fourth Fe site, Fe(4) is bonded to one O(2), one O(3), one O(5), one O(7), and one F(5) atom to form distorted FeO4F trigonal bipyramids that share  a cornercorner with one Mg(1)O4F2 octahedra,  a cornercorner with one Fe(2)O3F3 octahedra, corners with two equivalent Fe(3)O3F3 octahedra, corners with three equivalent Fe(6)O3F3 octahedra,  an edgeedge with one Mg(1)O4F2 octahedra,  an edgeedge with one Fe(1)O4F square pyramid, and  an edgeedge with one Fe(5)O4F trigonal bipyramid. The corner-sharing octahedral tilt angles range from 45-65°. In the fifth Fe site, Fe(5) is bonded to one O(1), one O(2), one O(5), one O(6), and one F(4) atom to form distorted FeO4F trigonal bipyramids that share  a cornercorner with one Mg(1)O4F2 octahedra,  a cornercorner with one Fe(6)O3F3 octahedra, corners with two equivalent Fe(3)O3F3 octahedra, corners with three equivalent Fe(2)O3F3 octahedra,  an edgeedge with one Mg(1)O4F2 octahedra,  an edgeedge with one Fe(1)O4F square pyramid, and  an edgeedge with one Fe(4)O4F trigonal bipyramid. The corner-sharing octahedral tilt angles range from 42-57°. In the sixth Fe site, Fe(6) is bonded to one O(3), one O(4), one O(7), one F(1), one F(4), and one F(5) atom to form FeO3F3 octahedra that share corners with three equivalent Fe(1)O4F square pyramids,  a cornercorner with one Fe(5)O4F trigonal bipyramid, corners with three equivalent Fe(4)O4F trigonal bipyramids,  an edgeedge with one Mg(1)O4F2 octahedra,  an edgeedge with one Fe(2)O3F3 octahedra, and  an edgeedge with one Fe(3)O3F3 octahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Fe(1), one Fe(2), and one Fe(5) atom to form a mixture of distorted corner and edge-sharing OMgFe3 trigonal pyramids. In the second O site, O(2) is bonded to one Mg(1), one Fe(3), one Fe(4), and one Fe(5) atom to form a mixture of corner and edge-sharing OMgFe3 trigonal pyramids. In the third O site, O(3) is bonded in a trigonal planar geometry to one Fe(2), one Fe(4), and one Fe(6) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(3), and one Fe(6) atom. In the fifth O site, O(5) is bonded to one Mg(1), one Fe(3), one Fe(4), and one Fe(5) atom to form a mixture of corner and edge-sharing OMgFe3 trigonal pyramids. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(2), and one Fe(5) atom. In the seventh O site, O(7) is bonded to one Mg(1), one Fe(1), one Fe(4), and one Fe(6) atom to form a mixture of distorted corner and edge-sharing OMgFe3 trigonal pyramids. There are five inequivalent F sites. In the first F site, F(1) is bonded in a distorted T-shaped geometry to one Mg(1), one Fe(3), and one Fe(6) atom. In the second F site, F(2) is bonded in a water-like geometry to one Fe(2) and one Fe(3) atom. In the third F site, F(3) is bonded in a 3-coordinate geometry to one Mg(1), one Fe(2), and one Fe(3) atom. In the fourth F site, F(4) is bonded in a distorted T-shaped geometry to one Fe(2), one Fe(5), and one Fe(6) atom. In the fifth F site, F(5) is bonded in a trigonal planar geometry to one Fe(1), one Fe(4), and one Fe(6) atom.
MgFe6O7F5 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(5), one O(7), one F(1), and one F(3) atom to form MgO4F2 octahedra that share corners with two equivalent Fe(1)O4F square pyramids,  a cornercorner with one Fe(4)O4F trigonal bipyramid,  a cornercorner with one Fe(5)O4F trigonal bipyramid,  an edgeedge with one Fe(2)O3F3 octahedra,  an edgeedge with one Fe(6)O3F3 octahedra, edges with two equivalent Fe(3)O3F3 octahedra,  an edgeedge with one Fe(4)O4F trigonal bipyramid, and  an edgeedge with one Fe(5)O4F trigonal bipyramid. The Mg(1)-O(1) bond length is 2.11 Å. The Mg(1)-O(2) bond length is 2.12 Å. The Mg(1)-O(5) bond length is 2.06 Å. The Mg(1)-O(7) bond length is 2.17 Å. The Mg(1)-F(1) bond length is 2.01 Å. The Mg(1)-F(3) 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(4), one O(6), one O(7), and one F(5) atom to form distorted FeO4F square pyramids that share  a cornercorner with one Fe(3)O3F3 octahedra, corners with two equivalent Mg(1)O4F2 octahedra, corners with two equivalent Fe(2)O3F3 octahedra, corners with three equivalent Fe(6)O3F3 octahedra,  an edgeedge with one Fe(4)O4F trigonal bipyramid, and  an edgeedge with one Fe(5)O4F trigonal bipyramid. The corner-sharing octahedral tilt angles range from 41-65°. The Fe(1)-O(1) bond length is 2.17 Å. The Fe(1)-O(4) bond length is 2.09 Å. The Fe(1)-O(6) bond length is 2.09 Å. The Fe(1)-O(7) bond length is 2.15 Å. The Fe(1)-F(5) bond length is 2.25 Å. In the second Fe site, Fe(2) is bonded to one O(1), one O(3), one O(6), one F(2), one F(3), and one F(4) atom to form FeO3F3 octahedra that share corners with two equivalent Fe(1)O4F square pyramids,  a cornercorner with one Fe(4)O4F trigonal bipyramid, corners with three equivalent Fe(5)O4F trigonal bipyramids,  an edgeedge with one Mg(1)O4F2 octahedra,  an edgeedge with one Fe(3)O3F3 octahedra, and  an edgeedge with one Fe(6)O3F3 octahedra. The Fe(2)-O(1) bond length is 1.99 Å. The Fe(2)-O(3) bond length is 1.93 Å. The Fe(2)-O(6) bond length is 1.91 Å. The Fe(2)-F(2) bond length is 1.98 Å. The Fe(2)-F(3) bond length is 2.20 Å. The Fe(2)-F(4) bond length is 2.26 Å. In the third Fe site, Fe(3) is bonded to one O(2), one O(4), one O(5), one F(1), one F(2), and one F(3) atom to form FeO3F3 octahedra that share  a cornercorner with one Fe(1)O4F square pyramid, corners with two equivalent Fe(4)O4F trigonal bipyramids, corners with two equivalent Fe(5)O4F trigonal bipyramids,  an edgeedge with one Fe(2)O3F3 octahedra,  an edgeedge with one Fe(6)O3F3 octahedra, and edges with two equivalent Mg(1)O4F2 octahedra. The Fe(3)-O(2) bond length is 2.03 Å. The Fe(3)-O(4) bond length is 1.90 Å. The Fe(3)-O(5) bond length is 2.06 Å. The Fe(3)-F(1) bond length is 2.06 Å. The Fe(3)-F(2) bond length is 2.07 Å. The Fe(3)-F(3) bond length is 2.02 Å. In the fourth Fe site, Fe(4) is bonded to one O(2), one O(3), one O(5), one O(7), and one F(5) atom to form distorted FeO4F trigonal bipyramids that share  a cornercorner with one Mg(1)O4F2 octahedra,  a cornercorner with one Fe(2)O3F3 octahedra, corners with two equivalent Fe(3)O3F3 octahedra, corners with three equivalent Fe(6)O3F3 octahedra,  an edgeedge with one Mg(1)O4F2 octahedra,  an edgeedge with one Fe(1)O4F square pyramid, and  an edgeedge with one Fe(5)O4F trigonal bipyramid. The corner-sharing octahedral tilt angles range from 45-65°. The Fe(4)-O(2) bond length is 2.01 Å. The Fe(4)-O(3) bond length is 1.91 Å. The Fe(4)-O(5) bond length is 2.02 Å. The Fe(4)-O(7) bond length is 2.02 Å. The Fe(4)-F(5) bond length is 2.10 Å. In the fifth Fe site, Fe(5) is bonded to one O(1), one O(2), one O(5), one O(6), and one F(4) atom to form distorted FeO4F trigonal bipyramids that share  a cornercorner with one Mg(1)O4F2 octahedra,  a cornercorner with one Fe(6)O3F3 octahedra, corners with two equivalent Fe(3)O3F3 octahedra, corners with three equivalent Fe(2)O3F3 octahedra,  an edgeedge with one Mg(1)O4F2 octahedra,  an edgeedge with one Fe(1)O4F square pyramid, and  an edgeedge with one Fe(4)O4F trigonal bipyramid. The corner-sharing octahedral tilt angles range from 42-57°. The Fe(5)-O(1) bond length is 2.03 Å. The Fe(5)-O(2) bond length is 2.06 Å. The Fe(5)-O(5) bond length is 2.01 Å. The Fe(5)-O(6) bond length is 1.89 Å. The Fe(5)-F(4) bond length is 2.02 Å. In the sixth Fe site, Fe(6) is bonded to one O(3), one O(4), one O(7), one F(1), one F(4), and one F(5) atom to form FeO3F3 octahedra that share corners with three equivalent Fe(1)O4F square pyramids,  a cornercorner with one Fe(5)O4F trigonal bipyramid, corners with three equivalent Fe(4)O4F trigonal bipyramids,  an edgeedge with one Mg(1)O4F2 octahedra,  an edgeedge with one Fe(2)O3F3 octahedra, and  an edgeedge with one Fe(3)O3F3 octahedra. The Fe(6)-O(3) bond length is 2.01 Å. The Fe(6)-O(4) bond length is 1.95 Å. The Fe(6)-O(7) bond length is 1.96 Å. The Fe(6)-F(1) bond length is 2.12 Å. The Fe(6)-F(4) bond length is 2.04 Å. The Fe(6)-F(5) bond length is 2.09 Å. There are seven inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Fe(1), one Fe(2), and one Fe(5) atom to form a mixture of distorted corner and edge-sharing OMgFe3 trigonal pyramids. In the second O site, O(2) is bonded to one Mg(1), one Fe(3), one Fe(4), and one Fe(5) atom to form a mixture of corner and edge-sharing OMgFe3 trigonal pyramids. In the third O site, O(3) is bonded in a trigonal planar geometry to one Fe(2), one Fe(4), and one Fe(6) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(3), and one Fe(6) atom. In the fifth O site, O(5) is bonded to one Mg(1), one Fe(3), one Fe(4), and one Fe(5) atom to form a mixture of corner and edge-sharing OMgFe3 trigonal pyramids. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(2), and one Fe(5) atom. In the seventh O site, O(7) is bonded to one Mg(1), one Fe(1), one Fe(4), and one Fe(6) atom to form a mixture of distorted corner and edge-sharing OMgFe3 trigonal pyramids. There are five inequivalent F sites. In the first F site, F(1) is bonded in a distorted T-shaped geometry to one Mg(1), one Fe(3), and one Fe(6) atom. In the second F site, F(2) is bonded in a water-like geometry to one Fe(2) and one Fe(3) atom. In the third F site, F(3) is bonded in a 3-coordinate geometry to one Mg(1), one Fe(2), and one Fe(3) atom. In the fourth F site, F(4) is bonded in a distorted T-shaped geometry to one Fe(2), one Fe(5), and one Fe(6) atom. In the fifth F site, F(5) is bonded in a trigonal planar geometry to one Fe(1), one Fe(4), and one Fe(6) atom.