MgFe6(OF)6 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent O(1), two equivalent F(2), and two equivalent F(3) atoms to form MgO2F4 octahedra that share corners with four equivalent Fe(3)O3F3 octahedra, edges with two equivalent Fe(2)O3F3 octahedra, edges with two equivalent Fe(1)O4F2 octahedra, and faces with two equivalent Fe(4)O2F4 octahedra. The corner-sharing octahedral tilt angles range from 48-50°. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent F(3) atoms to form FeO4F2 octahedra that share corners with four equivalent Fe(4)O2F4 octahedra, corners with four equivalent Fe(3)O3F3 octahedra, edges with two equivalent Mg(1)O2F4 octahedra, and edges with two equivalent Fe(2)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 39-56°. In the second Fe site, Fe(2) is bonded to one O(2), two equivalent O(3), one F(1), one F(2), and one F(3) atom to form distorted FeO3F3 octahedra that share corners with two equivalent Fe(4)O2F4 octahedra, corners with six equivalent Fe(3)O3F3 octahedra,  an edgeedge with one Mg(1)O2F4 octahedra,  an edgeedge with one Fe(2)O3F3 octahedra, and  an edgeedge with one Fe(1)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 37-57°. In the third Fe site, Fe(3) is bonded to one O(1), one O(2), one O(3), one F(2), and two equivalent F(1) atoms to form FeO3F3 octahedra that share corners with two equivalent Mg(1)O2F4 octahedra, corners with two equivalent Fe(1)O4F2 octahedra, corners with six equivalent Fe(2)O3F3 octahedra,  an edgeedge with one Fe(4)O2F4 octahedra, and  an edgeedge with one Fe(3)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 37-57°. In the fourth Fe site, Fe(4) is bonded to two equivalent O(1), two equivalent F(2), and two equivalent F(3) atoms to form FeO2F4 octahedra that share corners with four equivalent Fe(2)O3F3 octahedra, corners with four equivalent Fe(1)O4F2 octahedra, edges with two equivalent Fe(3)O3F3 octahedra, and faces with two equivalent Mg(1)O2F4 octahedra. The corner-sharing octahedral tilt angles range from 39-54°. There are three 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(1), one Fe(3), and one Fe(4) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Fe(1), one Fe(2), and one Fe(3) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Fe(3) and two equivalent Fe(2) atoms. There are three inequivalent F sites. In the first F site, F(1) is bonded in a distorted trigonal planar geometry to one Fe(2) and two equivalent Fe(3) atoms. In the second F site, F(2) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Fe(2), one Fe(3), and one Fe(4) atom. In the third F site, F(3) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Fe(1), one Fe(2), and one Fe(4) atom.
MgFe6(OF)6 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent O(1), two equivalent F(2), and two equivalent F(3) atoms to form MgO2F4 octahedra that share corners with four equivalent Fe(3)O3F3 octahedra, edges with two equivalent Fe(2)O3F3 octahedra, edges with two equivalent Fe(1)O4F2 octahedra, and faces with two equivalent Fe(4)O2F4 octahedra. The corner-sharing octahedral tilt angles range from 48-50°. Both Mg(1)-O(1) bond lengths are 2.02 Å. Both Mg(1)-F(2) bond lengths are 2.08 Å. Both Mg(1)-F(3) bond lengths are 2.00 Å. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent F(3) atoms to form FeO4F2 octahedra that share corners with four equivalent Fe(4)O2F4 octahedra, corners with four equivalent Fe(3)O3F3 octahedra, edges with two equivalent Mg(1)O2F4 octahedra, and edges with two equivalent Fe(2)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 39-56°. Both Fe(1)-O(1) bond lengths are 2.11 Å. Both Fe(1)-O(2) bond lengths are 2.03 Å. Both Fe(1)-F(3) bond lengths are 2.03 Å. In the second Fe site, Fe(2) is bonded to one O(2), two equivalent O(3), one F(1), one F(2), and one F(3) atom to form distorted FeO3F3 octahedra that share corners with two equivalent Fe(4)O2F4 octahedra, corners with six equivalent Fe(3)O3F3 octahedra,  an edgeedge with one Mg(1)O2F4 octahedra,  an edgeedge with one Fe(2)O3F3 octahedra, and  an edgeedge with one Fe(1)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 37-57°. The Fe(2)-O(2) bond length is 1.95 Å. There is one shorter (1.88 Å) and one longer (2.05 Å) Fe(2)-O(3) bond length. The Fe(2)-F(1) bond length is 2.05 Å. The Fe(2)-F(2) bond length is 2.32 Å. The Fe(2)-F(3) bond length is 2.27 Å. In the third Fe site, Fe(3) is bonded to one O(1), one O(2), one O(3), one F(2), and two equivalent F(1) atoms to form FeO3F3 octahedra that share corners with two equivalent Mg(1)O2F4 octahedra, corners with two equivalent Fe(1)O4F2 octahedra, corners with six equivalent Fe(2)O3F3 octahedra,  an edgeedge with one Fe(4)O2F4 octahedra, and  an edgeedge with one Fe(3)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 37-57°. The Fe(3)-O(1) bond length is 2.04 Å. The Fe(3)-O(2) bond length is 2.06 Å. The Fe(3)-O(3) bond length is 2.07 Å. The Fe(3)-F(2) bond length is 2.28 Å. There is one shorter (2.08 Å) and one longer (2.24 Å) Fe(3)-F(1) bond length. In the fourth Fe site, Fe(4) is bonded to two equivalent O(1), two equivalent F(2), and two equivalent F(3) atoms to form FeO2F4 octahedra that share corners with four equivalent Fe(2)O3F3 octahedra, corners with four equivalent Fe(1)O4F2 octahedra, edges with two equivalent Fe(3)O3F3 octahedra, and faces with two equivalent Mg(1)O2F4 octahedra. The corner-sharing octahedral tilt angles range from 39-54°. Both Fe(4)-O(1) bond lengths are 2.05 Å. Both Fe(4)-F(2) bond lengths are 2.09 Å. Both Fe(4)-F(3) bond lengths are 2.11 Å. There are three 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(1), one Fe(3), and one Fe(4) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Fe(1), one Fe(2), and one Fe(3) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Fe(3) and two equivalent Fe(2) atoms. There are three inequivalent F sites. In the first F site, F(1) is bonded in a distorted trigonal planar geometry to one Fe(2) and two equivalent Fe(3) atoms. In the second F site, F(2) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Fe(2), one Fe(3), and one Fe(4) atom. In the third F site, F(3) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Fe(1), one Fe(2), and one Fe(4) atom.