MgMn6(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 Mn(3)O3F3 octahedra, edges with two equivalent Mn(2)O3F3 octahedra, edges with two equivalent Mn(1)O4F2 octahedra, and faces with two equivalent Mn(4)O2F4 octahedra. The corner-sharing octahedral tilt angles range from 43-47°. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent F(3) atoms to form MnO4F2 octahedra that share corners with four equivalent Mn(4)O2F4 octahedra, corners with four equivalent Mn(3)O3F3 octahedra, edges with two equivalent Mg(1)O2F4 octahedra, and edges with two equivalent Mn(2)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 39-63°. In the second Mn site, Mn(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 MnO3F3 octahedra that share corners with two equivalent Mn(4)O2F4 octahedra, corners with six equivalent Mn(3)O3F3 octahedra,  an edgeedge with one Mg(1)O2F4 octahedra,  an edgeedge with one Mn(2)O3F3 octahedra, and  an edgeedge with one Mn(1)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 38-55°. In the third Mn site, Mn(3) is bonded to one O(1), one O(2), one O(3), one F(2), and two equivalent F(1) atoms to form distorted MnO3F3 octahedra that share corners with two equivalent Mg(1)O2F4 octahedra, corners with two equivalent Mn(1)O4F2 octahedra, corners with six equivalent Mn(2)O3F3 octahedra,  an edgeedge with one Mn(4)O2F4 octahedra, and  an edgeedge with one Mn(3)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 42-59°. In the fourth Mn site, Mn(4) is bonded to two equivalent O(1), two equivalent F(2), and two equivalent F(3) atoms to form MnO2F4 octahedra that share corners with four equivalent Mn(2)O3F3 octahedra, corners with four equivalent Mn(1)O4F2 octahedra, edges with two equivalent Mn(3)O3F3 octahedra, and faces with two equivalent Mg(1)O2F4 octahedra. The corner-sharing octahedral tilt angles range from 38-63°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Mg(1), one Mn(1), one Mn(3), and one Mn(4) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Mn(1), one Mn(2), and one Mn(3) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mn(3) and two equivalent Mn(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 Mn(2) and two equivalent Mn(3) atoms. In the second F site, F(2) is bonded in a 4-coordinate geometry to one Mg(1), one Mn(2), one Mn(3), and one Mn(4) atom. In the third F site, F(3) is bonded to one Mg(1), one Mn(1), one Mn(2), and one Mn(4) atom to form distorted corner-sharing FMgMn3 trigonal pyramids.
MgMn6(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 Mn(3)O3F3 octahedra, edges with two equivalent Mn(2)O3F3 octahedra, edges with two equivalent Mn(1)O4F2 octahedra, and faces with two equivalent Mn(4)O2F4 octahedra. The corner-sharing octahedral tilt angles range from 43-47°. Both Mg(1)-O(1) bond lengths are 2.05 Å. Both Mg(1)-F(2) bond lengths are 2.00 Å. Both Mg(1)-F(3) bond lengths are 2.02 Å. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent F(3) atoms to form MnO4F2 octahedra that share corners with four equivalent Mn(4)O2F4 octahedra, corners with four equivalent Mn(3)O3F3 octahedra, edges with two equivalent Mg(1)O2F4 octahedra, and edges with two equivalent Mn(2)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 39-63°. Both Mn(1)-O(1) bond lengths are 2.33 Å. Both Mn(1)-O(2) bond lengths are 2.14 Å. Both Mn(1)-F(3) bond lengths are 2.11 Å. In the second Mn site, Mn(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 MnO3F3 octahedra that share corners with two equivalent Mn(4)O2F4 octahedra, corners with six equivalent Mn(3)O3F3 octahedra,  an edgeedge with one Mg(1)O2F4 octahedra,  an edgeedge with one Mn(2)O3F3 octahedra, and  an edgeedge with one Mn(1)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 38-55°. The Mn(2)-O(2) bond length is 1.96 Å. There is one shorter (1.92 Å) and one longer (2.03 Å) Mn(2)-O(3) bond length. The Mn(2)-F(1) bond length is 2.22 Å. The Mn(2)-F(2) bond length is 2.42 Å. The Mn(2)-F(3) bond length is 2.11 Å. In the third Mn site, Mn(3) is bonded to one O(1), one O(2), one O(3), one F(2), and two equivalent F(1) atoms to form distorted MnO3F3 octahedra that share corners with two equivalent Mg(1)O2F4 octahedra, corners with two equivalent Mn(1)O4F2 octahedra, corners with six equivalent Mn(2)O3F3 octahedra,  an edgeedge with one Mn(4)O2F4 octahedra, and  an edgeedge with one Mn(3)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 42-59°. The Mn(3)-O(1) bond length is 1.96 Å. The Mn(3)-O(2) bond length is 2.00 Å. The Mn(3)-O(3) bond length is 2.00 Å. The Mn(3)-F(2) bond length is 2.53 Å. There is one shorter (2.06 Å) and one longer (2.18 Å) Mn(3)-F(1) bond length. In the fourth Mn site, Mn(4) is bonded to two equivalent O(1), two equivalent F(2), and two equivalent F(3) atoms to form MnO2F4 octahedra that share corners with four equivalent Mn(2)O3F3 octahedra, corners with four equivalent Mn(1)O4F2 octahedra, edges with two equivalent Mn(3)O3F3 octahedra, and faces with two equivalent Mg(1)O2F4 octahedra. The corner-sharing octahedral tilt angles range from 38-63°. Both Mn(4)-O(1) bond lengths are 2.10 Å. Both Mn(4)-F(2) bond lengths are 2.05 Å. Both Mn(4)-F(3) bond lengths are 2.13 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Mg(1), one Mn(1), one Mn(3), and one Mn(4) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Mn(1), one Mn(2), and one Mn(3) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mn(3) and two equivalent Mn(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 Mn(2) and two equivalent Mn(3) atoms. In the second F site, F(2) is bonded in a 4-coordinate geometry to one Mg(1), one Mn(2), one Mn(3), and one Mn(4) atom. In the third F site, F(3) is bonded to one Mg(1), one Mn(1), one Mn(2), and one Mn(4) atom to form distorted corner-sharing FMgMn3 trigonal pyramids.