MgFe6(O5F)2 crystallizes in the monoclinic Pm space group. Mg(1) is bonded to one O(5), one O(6), two equivalent O(10), and two equivalent F(1) atoms to form distorted edge-sharing MgO4F2 octahedra. There are six inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(3), one O(8), two equivalent O(2), and two equivalent O(9) atoms to form FeO6 octahedra that share corners with four equivalent Fe(6)O5F octahedra and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 50°. In the second Fe site, Fe(2) is bonded in a 6-coordinate geometry to one O(5), one O(6), two equivalent O(10), and two equivalent F(1) atoms. In the third Fe site, Fe(3) is bonded to one O(4), one O(7), two equivalent O(1), and two equivalent F(2) atoms to form FeO4F2 octahedra that share corners with four equivalent Fe(6)O5F octahedra and edges with two equivalent Fe(3)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 47-52°. In the fourth Fe site, Fe(4) is bonded in a 5-coordinate geometry to one O(9), two equivalent O(3), and two equivalent O(6) atoms. In the fifth Fe site, Fe(5) is bonded in a 6-coordinate geometry to one O(1), one O(10), two equivalent O(5), and two equivalent O(7) atoms. In the sixth Fe site, Fe(6) is bonded to one O(2), two equivalent O(4), two equivalent O(8), and one F(2) atom to form distorted FeO5F octahedra that share corners with four equivalent Fe(3)O4F2 octahedra, corners with four equivalent Fe(1)O6 octahedra, and edges with two equivalent Fe(6)O5F octahedra. The corner-sharing octahedral tilt angles range from 47-52°. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Fe(5) and two equivalent Fe(3) atoms. In the second O site, O(2) is bonded in a trigonal planar geometry to one Fe(6) and two equivalent Fe(1) atoms. In the third O site, O(3) is bonded in a trigonal planar geometry to one Fe(1) and two equivalent Fe(4) atoms. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Fe(3) and two equivalent Fe(6) atoms. In the fifth O site, O(5) is bonded to one Mg(1), one Fe(2), and two equivalent Fe(5) atoms to form distorted corner-sharing OMgFe3 tetrahedra. In the sixth O site, O(6) is bonded to one Mg(1), one Fe(2), and two equivalent Fe(4) atoms to form distorted corner-sharing OMgFe3 tetrahedra. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Fe(3) and two equivalent Fe(5) atoms. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Fe(1) and two equivalent Fe(6) atoms. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Fe(4) and two equivalent Fe(1) atoms. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to two equivalent Mg(1), one Fe(5), and two equivalent Fe(2) atoms. There are two inequivalent F sites. In the first F site, F(1) is bonded in a 4-coordinate geometry to two equivalent Mg(1) and two equivalent Fe(2) atoms. In the second F site, F(2) is bonded in a 3-coordinate geometry to one Fe(6) and two equivalent Fe(3) atoms.
MgFe6(O5F)2 crystallizes in the monoclinic Pm space group. Mg(1) is bonded to one O(5), one O(6), two equivalent O(10), and two equivalent F(1) atoms to form distorted edge-sharing MgO4F2 octahedra. The Mg(1)-O(5) bond length is 2.03 Å. The Mg(1)-O(6) bond length is 2.01 Å. Both Mg(1)-O(10) bond lengths are 2.21 Å. Both Mg(1)-F(1) bond lengths are 1.98 Å. There are six inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(3), one O(8), two equivalent O(2), and two equivalent O(9) atoms to form FeO6 octahedra that share corners with four equivalent Fe(6)O5F octahedra and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 50°. The Fe(1)-O(3) bond length is 1.98 Å. The Fe(1)-O(8) bond length is 2.04 Å. Both Fe(1)-O(2) bond lengths are 1.97 Å. Both Fe(1)-O(9) bond lengths are 2.00 Å. In the second Fe site, Fe(2) is bonded in a 6-coordinate geometry to one O(5), one O(6), two equivalent O(10), and two equivalent F(1) atoms. The Fe(2)-O(5) bond length is 1.89 Å. The Fe(2)-O(6) bond length is 2.02 Å. Both Fe(2)-O(10) bond lengths are 1.94 Å. Both Fe(2)-F(1) bond lengths are 2.45 Å. In the third Fe site, Fe(3) is bonded to one O(4), one O(7), two equivalent O(1), and two equivalent F(2) atoms to form FeO4F2 octahedra that share corners with four equivalent Fe(6)O5F octahedra and edges with two equivalent Fe(3)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 47-52°. The Fe(3)-O(4) bond length is 2.05 Å. The Fe(3)-O(7) bond length is 2.02 Å. Both Fe(3)-O(1) bond lengths are 1.96 Å. Both Fe(3)-F(2) bond lengths are 2.05 Å. In the fourth Fe site, Fe(4) is bonded in a 5-coordinate geometry to one O(9), two equivalent O(3), and two equivalent O(6) atoms. The Fe(4)-O(9) bond length is 1.91 Å. Both Fe(4)-O(3) bond lengths are 1.96 Å. Both Fe(4)-O(6) bond lengths are 2.07 Å. In the fifth Fe site, Fe(5) is bonded in a 6-coordinate geometry to one O(1), one O(10), two equivalent O(5), and two equivalent O(7) atoms. The Fe(5)-O(1) bond length is 1.94 Å. The Fe(5)-O(10) bond length is 2.56 Å. Both Fe(5)-O(5) bond lengths are 2.11 Å. Both Fe(5)-O(7) bond lengths are 1.94 Å. In the sixth Fe site, Fe(6) is bonded to one O(2), two equivalent O(4), two equivalent O(8), and one F(2) atom to form distorted FeO5F octahedra that share corners with four equivalent Fe(3)O4F2 octahedra, corners with four equivalent Fe(1)O6 octahedra, and edges with two equivalent Fe(6)O5F octahedra. The corner-sharing octahedral tilt angles range from 47-52°. The Fe(6)-O(2) bond length is 2.01 Å. Both Fe(6)-O(4) bond lengths are 1.94 Å. Both Fe(6)-O(8) bond lengths are 1.95 Å. The Fe(6)-F(2) bond length is 2.56 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Fe(5) and two equivalent Fe(3) atoms. In the second O site, O(2) is bonded in a trigonal planar geometry to one Fe(6) and two equivalent Fe(1) atoms. In the third O site, O(3) is bonded in a trigonal planar geometry to one Fe(1) and two equivalent Fe(4) atoms. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Fe(3) and two equivalent Fe(6) atoms. In the fifth O site, O(5) is bonded to one Mg(1), one Fe(2), and two equivalent Fe(5) atoms to form distorted corner-sharing OMgFe3 tetrahedra. In the sixth O site, O(6) is bonded to one Mg(1), one Fe(2), and two equivalent Fe(4) atoms to form distorted corner-sharing OMgFe3 tetrahedra. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Fe(3) and two equivalent Fe(5) atoms. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Fe(1) and two equivalent Fe(6) atoms. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Fe(4) and two equivalent Fe(1) atoms. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to two equivalent Mg(1), one Fe(5), and two equivalent Fe(2) atoms. There are two inequivalent F sites. In the first F site, F(1) is bonded in a 4-coordinate geometry to two equivalent Mg(1) and two equivalent Fe(2) atoms. In the second F site, F(2) is bonded in a 3-coordinate geometry to one Fe(6) and two equivalent Fe(3) atoms.