MgFe6O7F5 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(3), one O(5), one O(6), one O(7), one F(1), and one F(3) atom to form distorted MgO4F2 octahedra that share  a cornercorner with one Fe(4)O2F3 trigonal bipyramid, corners with two equivalent Fe(1)O4F trigonal bipyramids, corners with two equivalent Fe(2)O4F trigonal bipyramids,  an edgeedge with one Fe(6)O3F3 octahedra, edges with two equivalent Fe(5)O3F3 octahedra,  an edgeedge with one Fe(3)O4F trigonal bipyramid, and  a faceface with one Fe(3)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(5), one O(6), and one F(2) atom to form distorted FeO4F trigonal bipyramids that share  a cornercorner with one Fe(5)O3F3 octahedra, corners with two equivalent Mg(1)O4F2 octahedra, corners with two equivalent Fe(6)O3F3 octahedra, corners with two equivalent Fe(4)O2F3 trigonal bipyramids,  an edgeedge with one Fe(2)O4F trigonal bipyramid, and  an edgeedge with one Fe(3)O4F trigonal bipyramid. The corner-sharing octahedral tilt angles range from 13-58°. In the second Fe site, Fe(2) is bonded to one O(2), one O(3), one O(4), one O(7), and one F(2) atom to form distorted FeO4F trigonal bipyramids that share corners with two equivalent Mg(1)O4F2 octahedra, corners with two equivalent Fe(5)O3F3 octahedra, corners with three equivalent Fe(6)O3F3 octahedra,  a cornercorner with one Fe(4)O2F3 trigonal bipyramid,  an edgeedge with one Fe(1)O4F trigonal bipyramid, and  an edgeedge with one Fe(3)O4F trigonal bipyramid. The corner-sharing octahedral tilt angles range from 21-65°. In the third Fe site, Fe(3) is bonded to one O(3), one O(5), one O(6), one O(7), and one F(3) atom to form distorted FeO4F trigonal bipyramids that share corners with two equivalent Fe(6)O3F3 octahedra, corners with three equivalent Fe(5)O3F3 octahedra,  an edgeedge with one Mg(1)O4F2 octahedra,  an edgeedge with one Fe(1)O4F trigonal bipyramid,  an edgeedge with one Fe(2)O4F trigonal bipyramid, and  a faceface with one Mg(1)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 36-69°. In the fourth Fe site, Fe(4) is bonded to one O(1), one O(4), one F(1), one F(4), and one F(5) atom to form distorted FeO2F3 trigonal bipyramids that share  a cornercorner with one Mg(1)O4F2 octahedra,  a cornercorner with one Fe(2)O4F trigonal bipyramid, corners with two equivalent Fe(1)O4F trigonal bipyramids,  an edgeedge with one Fe(5)O3F3 octahedra, and  an edgeedge with one Fe(6)O3F3 octahedra. The corner-sharing octahedral tilt angles are 71°. In the fifth Fe site, Fe(5) is bonded to one O(2), one O(5), one O(7), one F(1), one F(3), and one F(4) atom to form FeO3F3 octahedra that share  a cornercorner with one Fe(1)O4F trigonal bipyramid, corners with two equivalent Fe(2)O4F trigonal bipyramids, corners with three equivalent Fe(3)O4F trigonal bipyramids,  an edgeedge with one Fe(6)O3F3 octahedra, edges with two equivalent Mg(1)O4F2 octahedra, and  an edgeedge with one Fe(4)O2F3 trigonal bipyramid. In the sixth Fe site, Fe(6) is bonded to one O(1), one O(2), one O(3), one F(2), one F(3), and one F(5) atom to form distorted FeO3F3 octahedra that share corners with two equivalent Fe(1)O4F trigonal bipyramids, corners with two equivalent Fe(3)O4F trigonal bipyramids, corners with three equivalent Fe(2)O4F trigonal bipyramids,  an edgeedge with one Mg(1)O4F2 octahedra,  an edgeedge with one Fe(5)O3F3 octahedra, and  an edgeedge with one Fe(4)O2F3 trigonal bipyramid. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(4), and one Fe(6) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Fe(2), 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(3), and one Fe(6) atom to form edge-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(4) atom. In the fifth O site, O(5) is bonded to one Mg(1), one Fe(1), one Fe(3), and one Fe(5) atom to form distorted edge-sharing OMgFe3 trigonal pyramids. In the sixth O site, O(6) is bonded in a T-shaped geometry to one Mg(1), one Fe(1), and one Fe(3) atom. In the seventh O site, O(7) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Fe(2), one Fe(3), and one Fe(5) atom. There are five inequivalent F sites. In the first F site, F(1) is bonded in a distorted trigonal non-coplanar 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 trigonal planar geometry to one Fe(1), one Fe(2), and one Fe(6) atom. In the third F site, F(3) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Fe(3), one Fe(5), and one Fe(6) atom. In the fourth F site, F(4) is bonded in a water-like geometry to one Fe(4) and one Fe(5) atom. In the fifth F site, F(5) is bonded in an L-shaped geometry to one Fe(4) and one Fe(6) atom.
MgFe6O7F5 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(3), one O(5), one O(6), one O(7), one F(1), and one F(3) atom to form distorted MgO4F2 octahedra that share  a cornercorner with one Fe(4)O2F3 trigonal bipyramid, corners with two equivalent Fe(1)O4F trigonal bipyramids, corners with two equivalent Fe(2)O4F trigonal bipyramids,  an edgeedge with one Fe(6)O3F3 octahedra, edges with two equivalent Fe(5)O3F3 octahedra,  an edgeedge with one Fe(3)O4F trigonal bipyramid, and  a faceface with one Fe(3)O4F trigonal bipyramid. The Mg(1)-O(3) bond length is 2.13 Å. The Mg(1)-O(5) bond length is 2.04 Å. The Mg(1)-O(6) bond length is 2.04 Å. The Mg(1)-O(7) bond length is 2.23 Å. The Mg(1)-F(1) bond length is 1.96 Å. The Mg(1)-F(3) 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(4), one O(5), one O(6), and one F(2) atom to form distorted FeO4F trigonal bipyramids that share  a cornercorner with one Fe(5)O3F3 octahedra, corners with two equivalent Mg(1)O4F2 octahedra, corners with two equivalent Fe(6)O3F3 octahedra, corners with two equivalent Fe(4)O2F3 trigonal bipyramids,  an edgeedge with one Fe(2)O4F trigonal bipyramid, and  an edgeedge with one Fe(3)O4F trigonal bipyramid. The corner-sharing octahedral tilt angles range from 13-58°. The Fe(1)-O(1) bond length is 1.97 Å. The Fe(1)-O(4) bond length is 1.99 Å. The Fe(1)-O(5) bond length is 1.99 Å. The Fe(1)-O(6) bond length is 1.91 Å. The Fe(1)-F(2) bond length is 2.35 Å. In the second Fe site, Fe(2) is bonded to one O(2), one O(3), one O(4), one O(7), and one F(2) atom to form distorted FeO4F trigonal bipyramids that share corners with two equivalent Mg(1)O4F2 octahedra, corners with two equivalent Fe(5)O3F3 octahedra, corners with three equivalent Fe(6)O3F3 octahedra,  a cornercorner with one Fe(4)O2F3 trigonal bipyramid,  an edgeedge with one Fe(1)O4F trigonal bipyramid, and  an edgeedge with one Fe(3)O4F trigonal bipyramid. The corner-sharing octahedral tilt angles range from 21-65°. The Fe(2)-O(2) bond length is 1.96 Å. The Fe(2)-O(3) bond length is 2.05 Å. The Fe(2)-O(4) bond length is 1.99 Å. The Fe(2)-O(7) bond length is 1.97 Å. The Fe(2)-F(2) bond length is 2.21 Å. In the third Fe site, Fe(3) is bonded to one O(3), one O(5), one O(6), one O(7), and one F(3) atom to form distorted FeO4F trigonal bipyramids that share corners with two equivalent Fe(6)O3F3 octahedra, corners with three equivalent Fe(5)O3F3 octahedra,  an edgeedge with one Mg(1)O4F2 octahedra,  an edgeedge with one Fe(1)O4F trigonal bipyramid,  an edgeedge with one Fe(2)O4F trigonal bipyramid, and  a faceface with one Mg(1)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 36-69°. The Fe(3)-O(3) bond length is 1.97 Å. The Fe(3)-O(5) bond length is 1.95 Å. The Fe(3)-O(6) bond length is 1.97 Å. The Fe(3)-O(7) bond length is 2.05 Å. The Fe(3)-F(3) bond length is 2.04 Å. In the fourth Fe site, Fe(4) is bonded to one O(1), one O(4), one F(1), one F(4), and one F(5) atom to form distorted FeO2F3 trigonal bipyramids that share  a cornercorner with one Mg(1)O4F2 octahedra,  a cornercorner with one Fe(2)O4F trigonal bipyramid, corners with two equivalent Fe(1)O4F trigonal bipyramids,  an edgeedge with one Fe(5)O3F3 octahedra, and  an edgeedge with one Fe(6)O3F3 octahedra. The corner-sharing octahedral tilt angles are 71°. The Fe(4)-O(1) bond length is 1.97 Å. The Fe(4)-O(4) bond length is 1.88 Å. The Fe(4)-F(1) bond length is 2.02 Å. The Fe(4)-F(4) bond length is 1.94 Å. The Fe(4)-F(5) bond length is 1.94 Å. In the fifth Fe site, Fe(5) is bonded to one O(2), one O(5), one O(7), one F(1), one F(3), and one F(4) atom to form FeO3F3 octahedra that share  a cornercorner with one Fe(1)O4F trigonal bipyramid, corners with two equivalent Fe(2)O4F trigonal bipyramids, corners with three equivalent Fe(3)O4F trigonal bipyramids,  an edgeedge with one Fe(6)O3F3 octahedra, edges with two equivalent Mg(1)O4F2 octahedra, and  an edgeedge with one Fe(4)O2F3 trigonal bipyramid. The Fe(5)-O(2) bond length is 2.07 Å. The Fe(5)-O(5) bond length is 2.19 Å. The Fe(5)-O(7) bond length is 2.18 Å. The Fe(5)-F(1) bond length is 2.15 Å. The Fe(5)-F(3) bond length is 2.17 Å. The Fe(5)-F(4) bond length is 2.04 Å. In the sixth Fe site, Fe(6) is bonded to one O(1), one O(2), one O(3), one F(2), one F(3), and one F(5) atom to form distorted FeO3F3 octahedra that share corners with two equivalent Fe(1)O4F trigonal bipyramids, corners with two equivalent Fe(3)O4F trigonal bipyramids, corners with three equivalent Fe(2)O4F trigonal bipyramids,  an edgeedge with one Mg(1)O4F2 octahedra,  an edgeedge with one Fe(5)O3F3 octahedra, and  an edgeedge with one Fe(4)O2F3 trigonal bipyramid. The Fe(6)-O(1) bond length is 1.91 Å. The Fe(6)-O(2) bond length is 1.93 Å. The Fe(6)-O(3) bond length is 2.06 Å. The Fe(6)-F(2) bond length is 2.04 Å. The Fe(6)-F(3) bond length is 2.34 Å. The Fe(6)-F(5) bond length is 2.04 Å. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(4), and one Fe(6) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Fe(2), 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(3), and one Fe(6) atom to form edge-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(4) atom. In the fifth O site, O(5) is bonded to one Mg(1), one Fe(1), one Fe(3), and one Fe(5) atom to form distorted edge-sharing OMgFe3 trigonal pyramids. In the sixth O site, O(6) is bonded in a T-shaped geometry to one Mg(1), one Fe(1), and one Fe(3) atom. In the seventh O site, O(7) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Fe(2), one Fe(3), and one Fe(5) atom. There are five inequivalent F sites. In the first F site, F(1) is bonded in a distorted trigonal non-coplanar 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 trigonal planar geometry to one Fe(1), one Fe(2), and one Fe(6) atom. In the third F site, F(3) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Fe(3), one Fe(5), and one Fe(6) atom. In the fourth F site, F(4) is bonded in a water-like geometry to one Fe(4) and one Fe(5) atom. In the fifth F site, F(5) is bonded in an L-shaped geometry to one Fe(4) and one Fe(6) atom.