MgFe6O7F5 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 4-coordinate geometry to one O(4), one O(5), one O(6), one F(1), and one F(4) atom. There are six inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(3), one O(4), one O(5), one F(2), one F(3), and one F(5) atom to form FeO3F3 octahedra that share corners with two equivalent Fe(6)O3F3 octahedra,  a cornercorner with one Fe(5)O3F2 trigonal bipyramid,  an edgeedge with one Fe(3)O4F2 octahedra, and  an edgeedge with one Fe(2)O5F octahedra. The corner-sharing octahedral tilt angles are 49°. In the second Fe site, Fe(2) is bonded to one O(1), one O(2), one O(3), one O(6), one O(7), and one F(3) atom to form FeO5F octahedra that share corners with four equivalent Fe(6)O3F3 octahedra, corners with two equivalent Fe(5)O3F2 trigonal bipyramids,  an edgeedge with one Fe(1)O3F3 octahedra, and  an edgeedge with one Fe(3)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 40-59°. In the third Fe site, Fe(3) is bonded to one O(2), one O(4), one O(5), one O(6), one F(1), and one F(4) atom to form distorted FeO4F2 octahedra that share corners with two equivalent Fe(6)O3F3 octahedra, corners with four equivalent Fe(5)O3F2 trigonal bipyramids,  an edgeedge with one Fe(1)O3F3 octahedra, and  an edgeedge with one Fe(2)O5F octahedra. The corner-sharing octahedral tilt angles range from 50-52°. In the fourth Fe site, Fe(4) is bonded in a 6-coordinate geometry to one O(3), one O(5), one O(7), one F(1), one F(2), and one F(5) atom. In the fifth Fe site, Fe(5) is bonded to one O(1), one O(4), one O(6), one F(1), and one F(4) atom to form distorted FeO3F2 trigonal bipyramids that share  a cornercorner with one Fe(1)O3F3 octahedra, corners with two equivalent Fe(2)O5F octahedra, corners with four equivalent Fe(3)O4F2 octahedra, and  an edgeedge with one Fe(6)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 36-70°. In the sixth Fe site, Fe(6) is bonded to one O(1), one O(2), one O(7), one F(2), one F(3), and one F(4) atom to form FeO3F3 octahedra that share corners with two equivalent Fe(1)O3F3 octahedra, corners with two equivalent Fe(3)O4F2 octahedra, corners with four equivalent Fe(2)O5F octahedra, and  an edgeedge with one Fe(5)O3F2 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 40-59°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Fe(2), one Fe(5), and one Fe(6) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Fe(2), one Fe(3), and one Fe(6) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Fe(1), one Fe(2), and one Fe(4) atom. In the fourth O site, O(4) is bonded to one Mg(1), one Fe(1), one Fe(3), and one Fe(5) atom to form distorted OMgFe3 trigonal pyramids that share  a cornercorner with one F(1)MgFe3 trigonal pyramid and  an edgeedge with one F(1)MgFe3 trigonal pyramid. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(1), one Fe(3), and one Fe(4) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(2), one Fe(3), and one Fe(5) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Fe(2), one Fe(4), and one Fe(6) atom. There are five inequivalent F sites. In the first F site, F(1) is bonded to one Mg(1), one Fe(3), one Fe(4), and one Fe(5) atom to form distorted FMgFe3 trigonal pyramids that share  a cornercorner with one O(4)MgFe3 trigonal pyramid and  an edgeedge with one O(4)MgFe3 trigonal pyramid. In the second F site, F(2) is bonded in a distorted T-shaped geometry to one Fe(1), one Fe(4), and one Fe(6) atom. In the third F site, F(3) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(2), and one Fe(6) atom. In the fourth F site, F(4) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(3), one Fe(5), and one Fe(6) atom. In the fifth F site, F(5) is bonded in a bent 120 degrees geometry to one Fe(1) and one Fe(4) atom.
MgFe6O7F5 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 4-coordinate geometry to one O(4), one O(5), one O(6), one F(1), and one F(4) atom. The Mg(1)-O(4) bond length is 1.97 Å. The Mg(1)-O(5) bond length is 1.99 Å. The Mg(1)-O(6) bond length is 2.37 Å. The Mg(1)-F(1) bond length is 1.94 Å. The Mg(1)-F(4) bond length is 1.96 Å. There are six inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(3), one O(4), one O(5), one F(2), one F(3), and one F(5) atom to form FeO3F3 octahedra that share corners with two equivalent Fe(6)O3F3 octahedra,  a cornercorner with one Fe(5)O3F2 trigonal bipyramid,  an edgeedge with one Fe(3)O4F2 octahedra, and  an edgeedge with one Fe(2)O5F octahedra. The corner-sharing octahedral tilt angles are 49°. The Fe(1)-O(3) bond length is 1.96 Å. The Fe(1)-O(4) bond length is 1.98 Å. The Fe(1)-O(5) bond length is 2.07 Å. The Fe(1)-F(2) bond length is 2.19 Å. The Fe(1)-F(3) bond length is 2.13 Å. The Fe(1)-F(5) bond length is 2.06 Å. In the second Fe site, Fe(2) is bonded to one O(1), one O(2), one O(3), one O(6), one O(7), and one F(3) atom to form FeO5F octahedra that share corners with four equivalent Fe(6)O3F3 octahedra, corners with two equivalent Fe(5)O3F2 trigonal bipyramids,  an edgeedge with one Fe(1)O3F3 octahedra, and  an edgeedge with one Fe(3)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 40-59°. The Fe(2)-O(1) bond length is 2.14 Å. The Fe(2)-O(2) bond length is 1.97 Å. The Fe(2)-O(3) bond length is 2.05 Å. The Fe(2)-O(6) bond length is 2.14 Å. The Fe(2)-O(7) bond length is 2.12 Å. The Fe(2)-F(3) bond length is 2.16 Å. In the third Fe site, Fe(3) is bonded to one O(2), one O(4), one O(5), one O(6), one F(1), and one F(4) atom to form distorted FeO4F2 octahedra that share corners with two equivalent Fe(6)O3F3 octahedra, corners with four equivalent Fe(5)O3F2 trigonal bipyramids,  an edgeedge with one Fe(1)O3F3 octahedra, and  an edgeedge with one Fe(2)O5F octahedra. The corner-sharing octahedral tilt angles range from 50-52°. The Fe(3)-O(2) bond length is 2.00 Å. The Fe(3)-O(4) bond length is 2.10 Å. The Fe(3)-O(5) bond length is 2.08 Å. The Fe(3)-O(6) bond length is 2.05 Å. The Fe(3)-F(1) bond length is 2.26 Å. The Fe(3)-F(4) bond length is 2.43 Å. In the fourth Fe site, Fe(4) is bonded in a 6-coordinate geometry to one O(3), one O(5), one O(7), one F(1), one F(2), and one F(5) atom. The Fe(4)-O(3) bond length is 1.99 Å. The Fe(4)-O(5) bond length is 2.08 Å. The Fe(4)-O(7) bond length is 1.87 Å. The Fe(4)-F(1) bond length is 2.39 Å. The Fe(4)-F(2) bond length is 2.25 Å. The Fe(4)-F(5) bond length is 1.97 Å. In the fifth Fe site, Fe(5) is bonded to one O(1), one O(4), one O(6), one F(1), and one F(4) atom to form distorted FeO3F2 trigonal bipyramids that share  a cornercorner with one Fe(1)O3F3 octahedra, corners with two equivalent Fe(2)O5F octahedra, corners with four equivalent Fe(3)O4F2 octahedra, and  an edgeedge with one Fe(6)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 36-70°. The Fe(5)-O(1) bond length is 1.87 Å. The Fe(5)-O(4) bond length is 2.04 Å. The Fe(5)-O(6) bond length is 1.90 Å. The Fe(5)-F(1) bond length is 2.04 Å. The Fe(5)-F(4) bond length is 2.12 Å. In the sixth Fe site, Fe(6) is bonded to one O(1), one O(2), one O(7), one F(2), one F(3), and one F(4) atom to form FeO3F3 octahedra that share corners with two equivalent Fe(1)O3F3 octahedra, corners with two equivalent Fe(3)O4F2 octahedra, corners with four equivalent Fe(2)O5F octahedra, and  an edgeedge with one Fe(5)O3F2 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 40-59°. The Fe(6)-O(1) bond length is 2.00 Å. The Fe(6)-O(2) bond length is 1.93 Å. The Fe(6)-O(7) bond length is 2.03 Å. The Fe(6)-F(2) bond length is 2.02 Å. The Fe(6)-F(3) bond length is 2.10 Å. The Fe(6)-F(4) bond length is 2.15 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(2), one Fe(5), and one Fe(6) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Fe(2), one Fe(3), and one Fe(6) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Fe(1), one Fe(2), and one Fe(4) atom. In the fourth O site, O(4) is bonded to one Mg(1), one Fe(1), one Fe(3), and one Fe(5) atom to form distorted OMgFe3 trigonal pyramids that share  a cornercorner with one F(1)MgFe3 trigonal pyramid and  an edgeedge with one F(1)MgFe3 trigonal pyramid. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(1), one Fe(3), and one Fe(4) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(2), one Fe(3), and one Fe(5) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Fe(2), one Fe(4), and one Fe(6) atom. There are five inequivalent F sites. In the first F site, F(1) is bonded to one Mg(1), one Fe(3), one Fe(4), and one Fe(5) atom to form distorted FMgFe3 trigonal pyramids that share  a cornercorner with one O(4)MgFe3 trigonal pyramid and  an edgeedge with one O(4)MgFe3 trigonal pyramid. In the second F site, F(2) is bonded in a distorted T-shaped geometry to one Fe(1), one Fe(4), and one Fe(6) atom. In the third F site, F(3) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(2), and one Fe(6) atom. In the fourth F site, F(4) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(3), one Fe(5), and one Fe(6) atom. In the fifth F site, F(5) is bonded in a bent 120 degrees geometry to one Fe(1) and one Fe(4) atom.