MgFe6O7F5 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(4), one O(7), one F(1), one F(3), and one F(5) atom to form distorted MgO3F3 octahedra that share corners with two equivalent Fe(3)O3F3 octahedra,  a cornercorner with one Fe(1)O3F2 trigonal bipyramid,  a cornercorner with one Fe(4)O4F trigonal bipyramid,  a cornercorner with one Fe(6)O4F trigonal bipyramid,  an edgeedge with one Fe(4)O4F trigonal bipyramid,  an edgeedge with one Fe(6)O4F trigonal bipyramid, and faces with two equivalent Fe(2)O3F3 octahedra. The corner-sharing octahedral tilt angles are 47°. There are six inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(2), one O(3), one O(6), one F(1), and one F(4) atom to form FeO3F2 trigonal bipyramids that share  a cornercorner with one Mg(1)O3F3 octahedra,  a cornercorner with one Fe(2)O3F3 octahedra, corners with two equivalent Fe(4)O4F trigonal bipyramids, corners with three equivalent Fe(5)O4F trigonal bipyramids, and  an edgeedge with one Fe(3)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 42-80°. In the second Fe site, Fe(2) is bonded to one O(1), one O(4), one O(7), one F(1), one F(3), and one F(5) atom to form FeO3F3 octahedra that share  a cornercorner with one Fe(1)O3F2 trigonal bipyramid, corners with three equivalent Fe(4)O4F trigonal bipyramids, corners with three equivalent Fe(6)O4F trigonal bipyramids,  an edgeedge with one Fe(3)O3F3 octahedra, and faces with two equivalent Mg(1)O3F3 octahedra. In the third Fe site, Fe(3) is bonded to one O(1), one O(2), one O(5), one F(2), one F(4), and one F(5) atom to form FeO3F3 octahedra that share corners with two equivalent Mg(1)O3F3 octahedra, corners with three equivalent Fe(5)O4F trigonal bipyramids, corners with three equivalent Fe(6)O4F trigonal bipyramids,  an edgeedge with one Fe(2)O3F3 octahedra, and  an edgeedge with one Fe(1)O3F2 trigonal bipyramid. The corner-sharing octahedral tilt angles are 47°. In the fourth Fe site, Fe(4) is bonded to one O(3), one O(4), one O(6), one O(7), and one F(3) atom to form distorted FeO4F trigonal bipyramids that share  a cornercorner with one Mg(1)O3F3 octahedra, corners with three equivalent Fe(2)O3F3 octahedra, corners with two equivalent Fe(1)O3F2 trigonal bipyramids,  an edgeedge with one Mg(1)O3F3 octahedra,  an edgeedge with one Fe(5)O4F trigonal bipyramid, and  an edgeedge with one Fe(6)O4F trigonal bipyramid. The corner-sharing octahedral tilt angles range from 23-60°. In the fifth Fe site, Fe(5) is bonded to one O(2), one O(3), one O(5), one O(6), and one F(2) atom to form distorted FeO4F trigonal bipyramids that share corners with three equivalent Fe(3)O3F3 octahedra, corners with three equivalent Fe(1)O3F2 trigonal bipyramids,  an edgeedge with one Fe(4)O4F trigonal bipyramid, and  an edgeedge with one Fe(6)O4F trigonal bipyramid. The corner-sharing octahedral tilt angles range from 44-56°. In the sixth Fe site, Fe(6) is bonded to one O(1), one O(4), one O(5), one O(7), and one F(2) atom to form FeO4F trigonal bipyramids that share  a cornercorner with one Mg(1)O3F3 octahedra, corners with three equivalent Fe(2)O3F3 octahedra, corners with three equivalent Fe(3)O3F3 octahedra,  an edgeedge with one Mg(1)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 43-72°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Fe(2), one Fe(3), and one Fe(6) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(3), and one Fe(5) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(4), and one Fe(5) atom. In the fourth O site, O(4) is bonded to one Mg(1), one Fe(2), one Fe(4), and one Fe(6) atom to form a mixture of distorted corner and edge-sharing OMgFe3 trigonal pyramids. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Fe(3), one Fe(5), and one Fe(6) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(4), and one Fe(5) atom. In the seventh O site, O(7) is bonded to one Mg(1), one Fe(2), 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 3-coordinate geometry to one Mg(1), one Fe(1), and one Fe(2) atom. In the second F site, F(2) is bonded in a distorted T-shaped geometry to one Fe(3), one Fe(5), and one Fe(6) atom. In the third F site, F(3) is bonded in a distorted T-shaped geometry to one Mg(1), one Fe(2), and one Fe(4) atom. In the fourth F site, F(4) is bonded in an L-shaped geometry to one Fe(1) and one Fe(3) atom. In the fifth F site, F(5) is bonded in a distorted T-shaped geometry to one Mg(1), one Fe(2), and one Fe(3) atom.
MgFe6O7F5 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(4), one O(7), one F(1), one F(3), and one F(5) atom to form distorted MgO3F3 octahedra that share corners with two equivalent Fe(3)O3F3 octahedra,  a cornercorner with one Fe(1)O3F2 trigonal bipyramid,  a cornercorner with one Fe(4)O4F trigonal bipyramid,  a cornercorner with one Fe(6)O4F trigonal bipyramid,  an edgeedge with one Fe(4)O4F trigonal bipyramid,  an edgeedge with one Fe(6)O4F trigonal bipyramid, and faces with two equivalent Fe(2)O3F3 octahedra. The corner-sharing octahedral tilt angles are 47°. The Mg(1)-O(1) bond length is 2.08 Å. The Mg(1)-O(4) bond length is 1.98 Å. The Mg(1)-O(7) bond length is 1.96 Å. The Mg(1)-F(1) bond length is 2.35 Å. The Mg(1)-F(3) bond length is 2.05 Å. The Mg(1)-F(5) bond length is 2.00 Å. There are six inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(2), one O(3), one O(6), one F(1), and one F(4) atom to form FeO3F2 trigonal bipyramids that share  a cornercorner with one Mg(1)O3F3 octahedra,  a cornercorner with one Fe(2)O3F3 octahedra, corners with two equivalent Fe(4)O4F trigonal bipyramids, corners with three equivalent Fe(5)O4F trigonal bipyramids, and  an edgeedge with one Fe(3)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 42-80°. The Fe(1)-O(2) bond length is 1.93 Å. The Fe(1)-O(3) bond length is 2.01 Å. The Fe(1)-O(6) bond length is 1.99 Å. The Fe(1)-F(1) bond length is 2.02 Å. The Fe(1)-F(4) bond length is 1.96 Å. In the second Fe site, Fe(2) is bonded to one O(1), one O(4), one O(7), one F(1), one F(3), and one F(5) atom to form FeO3F3 octahedra that share  a cornercorner with one Fe(1)O3F2 trigonal bipyramid, corners with three equivalent Fe(4)O4F trigonal bipyramids, corners with three equivalent Fe(6)O4F trigonal bipyramids,  an edgeedge with one Fe(3)O3F3 octahedra, and faces with two equivalent Mg(1)O3F3 octahedra. The Fe(2)-O(1) bond length is 2.14 Å. The Fe(2)-O(4) bond length is 2.01 Å. The Fe(2)-O(7) bond length is 2.03 Å. The Fe(2)-F(1) bond length is 2.12 Å. The Fe(2)-F(3) bond length is 2.28 Å. The Fe(2)-F(5) bond length is 2.14 Å. In the third Fe site, Fe(3) is bonded to one O(1), one O(2), one O(5), one F(2), one F(4), and one F(5) atom to form FeO3F3 octahedra that share corners with two equivalent Mg(1)O3F3 octahedra, corners with three equivalent Fe(5)O4F trigonal bipyramids, corners with three equivalent Fe(6)O4F trigonal bipyramids,  an edgeedge with one Fe(2)O3F3 octahedra, and  an edgeedge with one Fe(1)O3F2 trigonal bipyramid. The corner-sharing octahedral tilt angles are 47°. The Fe(3)-O(1) bond length is 1.99 Å. The Fe(3)-O(2) bond length is 1.98 Å. The Fe(3)-O(5) bond length is 1.95 Å. The Fe(3)-F(2) bond length is 2.16 Å. The Fe(3)-F(4) bond length is 2.04 Å. The Fe(3)-F(5) bond length is 2.15 Å. In the fourth Fe site, Fe(4) is bonded to one O(3), one O(4), one O(6), one O(7), and one F(3) atom to form distorted FeO4F trigonal bipyramids that share  a cornercorner with one Mg(1)O3F3 octahedra, corners with three equivalent Fe(2)O3F3 octahedra, corners with two equivalent Fe(1)O3F2 trigonal bipyramids,  an edgeedge with one Mg(1)O3F3 octahedra,  an edgeedge with one Fe(5)O4F trigonal bipyramid, and  an edgeedge with one Fe(6)O4F trigonal bipyramid. The corner-sharing octahedral tilt angles range from 23-60°. The Fe(4)-O(3) bond length is 1.95 Å. The Fe(4)-O(4) bond length is 1.98 Å. The Fe(4)-O(6) bond length is 1.96 Å. The Fe(4)-O(7) bond length is 2.07 Å. The Fe(4)-F(3) bond length is 2.02 Å. In the fifth Fe site, Fe(5) is bonded to one O(2), one O(3), one O(5), one O(6), and one F(2) atom to form distorted FeO4F trigonal bipyramids that share corners with three equivalent Fe(3)O3F3 octahedra, corners with three equivalent Fe(1)O3F2 trigonal bipyramids,  an edgeedge with one Fe(4)O4F trigonal bipyramid, and  an edgeedge with one Fe(6)O4F trigonal bipyramid. The corner-sharing octahedral tilt angles range from 44-56°. The Fe(5)-O(2) bond length is 1.95 Å. The Fe(5)-O(3) bond length is 1.98 Å. The Fe(5)-O(5) bond length is 1.98 Å. The Fe(5)-O(6) bond length is 1.99 Å. The Fe(5)-F(2) bond length is 2.29 Å. In the sixth Fe site, Fe(6) is bonded to one O(1), one O(4), one O(5), one O(7), and one F(2) atom to form FeO4F trigonal bipyramids that share  a cornercorner with one Mg(1)O3F3 octahedra, corners with three equivalent Fe(2)O3F3 octahedra, corners with three equivalent Fe(3)O3F3 octahedra,  an edgeedge with one Mg(1)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 43-72°. The Fe(6)-O(1) bond length is 1.96 Å. The Fe(6)-O(4) bond length is 2.03 Å. The Fe(6)-O(5) bond length is 1.96 Å. The Fe(6)-O(7) bond length is 1.97 Å. The Fe(6)-F(2) bond length is 2.02 Å. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Fe(2), one Fe(3), and one Fe(6) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(3), and one Fe(5) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(4), and one Fe(5) atom. In the fourth O site, O(4) is bonded to one Mg(1), one Fe(2), one Fe(4), and one Fe(6) atom to form a mixture of distorted corner and edge-sharing OMgFe3 trigonal pyramids. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Fe(3), one Fe(5), and one Fe(6) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(4), and one Fe(5) atom. In the seventh O site, O(7) is bonded to one Mg(1), one Fe(2), 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 3-coordinate geometry to one Mg(1), one Fe(1), and one Fe(2) atom. In the second F site, F(2) is bonded in a distorted T-shaped geometry to one Fe(3), one Fe(5), and one Fe(6) atom. In the third F site, F(3) is bonded in a distorted T-shaped geometry to one Mg(1), one Fe(2), and one Fe(4) atom. In the fourth F site, F(4) is bonded in an L-shaped geometry to one Fe(1) and one Fe(3) atom. In the fifth F site, F(5) is bonded in a distorted T-shaped geometry to one Mg(1), one Fe(2), and one Fe(3) atom.