MgMn4(OF)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(4), one F(1), one F(2), and one F(4) atom to form MgO3F3 octahedra that share corners with two equivalent Mn(3)O2F2 tetrahedra, edges with two equivalent Mn(1)O3F3 octahedra, and edges with two equivalent Mn(4)O3F3 octahedra. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(2), one O(3), one F(1), one F(2), and one F(3) atom to form distorted MnO3F3 octahedra that share corners with three equivalent Mn(3)O2F2 tetrahedra, edges with two equivalent Mg(1)O3F3 octahedra, and edges with two equivalent Mn(4)O3F3 octahedra. In the second Mn site, Mn(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one F(2), and one F(4) atom. In the third Mn site, Mn(3) is bonded to one O(3), one O(4), one F(1), and one F(3) atom to form MnO2F2 tetrahedra that share corners with two equivalent Mg(1)O3F3 octahedra, corners with three equivalent Mn(1)O3F3 octahedra, and corners with three equivalent Mn(4)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 51-66°. In the fourth Mn site, Mn(4) is bonded to one O(2), one O(3), one O(4), one F(2), one F(3), and one F(4) atom to form MnO3F3 octahedra that share corners with three equivalent Mn(3)O2F2 tetrahedra, edges with two equivalent Mg(1)O3F3 octahedra, and edges with two equivalent Mn(1)O3F3 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a T-shaped geometry to one Mg(1), one Mn(1), and one Mn(2) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Mn(1), one Mn(2), and one Mn(4) atom. In the third O site, O(3) is bonded to one Mn(1), one Mn(2), one Mn(3), and one Mn(4) atom to form a mixture of distorted corner and edge-sharing OMn4 tetrahedra. In the fourth O site, O(4) is bonded to one Mg(1), one Mn(2), one Mn(3), and one Mn(4) atom to form a mixture of distorted corner and edge-sharing OMgMn3 tetrahedra. There are four inequivalent F sites. In the first F site, F(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mn(1), and one Mn(3) atom. In the second F site, F(2) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Mn(1), one Mn(2), and one Mn(4) atom. In the third F site, F(3) is bonded in a trigonal planar geometry to one Mn(1), one Mn(3), and one Mn(4) atom. In the fourth F site, F(4) is bonded in a distorted water-like geometry to one Mg(1), one Mn(2), and one Mn(4) atom.
MgMn4(OF)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(4), one F(1), one F(2), and one F(4) atom to form MgO3F3 octahedra that share corners with two equivalent Mn(3)O2F2 tetrahedra, edges with two equivalent Mn(1)O3F3 octahedra, and edges with two equivalent Mn(4)O3F3 octahedra. The Mg(1)-O(1) bond length is 1.99 Å. The Mg(1)-O(2) bond length is 2.13 Å. The Mg(1)-O(4) bond length is 2.16 Å. The Mg(1)-F(1) bond length is 2.02 Å. The Mg(1)-F(2) bond length is 2.02 Å. The Mg(1)-F(4) bond length is 2.07 Å. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(2), one O(3), one F(1), one F(2), and one F(3) atom to form distorted MnO3F3 octahedra that share corners with three equivalent Mn(3)O2F2 tetrahedra, edges with two equivalent Mg(1)O3F3 octahedra, and edges with two equivalent Mn(4)O3F3 octahedra. The Mn(1)-O(1) bond length is 1.99 Å. The Mn(1)-O(2) bond length is 2.09 Å. The Mn(1)-O(3) bond length is 2.29 Å. The Mn(1)-F(1) bond length is 2.30 Å. The Mn(1)-F(2) bond length is 2.35 Å. The Mn(1)-F(3) bond length is 2.20 Å. In the second Mn site, Mn(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one F(2), and one F(4) atom. The Mn(2)-O(1) bond length is 1.87 Å. The Mn(2)-O(2) bond length is 1.92 Å. The Mn(2)-O(3) bond length is 2.04 Å. The Mn(2)-O(4) bond length is 1.98 Å. The Mn(2)-F(2) bond length is 2.41 Å. The Mn(2)-F(4) bond length is 2.72 Å. In the third Mn site, Mn(3) is bonded to one O(3), one O(4), one F(1), and one F(3) atom to form MnO2F2 tetrahedra that share corners with two equivalent Mg(1)O3F3 octahedra, corners with three equivalent Mn(1)O3F3 octahedra, and corners with three equivalent Mn(4)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 51-66°. The Mn(3)-O(3) bond length is 2.07 Å. The Mn(3)-O(4) bond length is 2.04 Å. The Mn(3)-F(1) bond length is 2.12 Å. The Mn(3)-F(3) bond length is 2.12 Å. In the fourth Mn site, Mn(4) is bonded to one O(2), one O(3), one O(4), one F(2), one F(3), and one F(4) atom to form MnO3F3 octahedra that share corners with three equivalent Mn(3)O2F2 tetrahedra, edges with two equivalent Mg(1)O3F3 octahedra, and edges with two equivalent Mn(1)O3F3 octahedra. The Mn(4)-O(2) bond length is 2.11 Å. The Mn(4)-O(3) bond length is 1.91 Å. The Mn(4)-O(4) bond length is 1.97 Å. The Mn(4)-F(2) bond length is 2.21 Å. The Mn(4)-F(3) bond length is 2.06 Å. The Mn(4)-F(4) bond length is 1.93 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a T-shaped geometry to one Mg(1), one Mn(1), and one Mn(2) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Mn(1), one Mn(2), and one Mn(4) atom. In the third O site, O(3) is bonded to one Mn(1), one Mn(2), one Mn(3), and one Mn(4) atom to form a mixture of distorted corner and edge-sharing OMn4 tetrahedra. In the fourth O site, O(4) is bonded to one Mg(1), one Mn(2), one Mn(3), and one Mn(4) atom to form a mixture of distorted corner and edge-sharing OMgMn3 tetrahedra. There are four inequivalent F sites. In the first F site, F(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one Mn(1), and one Mn(3) atom. In the second F site, F(2) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Mn(1), one Mn(2), and one Mn(4) atom. In the third F site, F(3) is bonded in a trigonal planar geometry to one Mn(1), one Mn(3), and one Mn(4) atom. In the fourth F site, F(4) is bonded in a distorted water-like geometry to one Mg(1), one Mn(2), and one Mn(4) atom.