MgMn4(OF2)4 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent F(2), two equivalent F(3), and two equivalent F(4) atoms to form MgF6 octahedra that share corners with two equivalent Mn(1)OF4 trigonal bipyramids and edges with two equivalent Mn(1)OF4 trigonal bipyramids. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(2), one F(1), one F(2), one F(3), and one F(4) atom to form MnOF4 trigonal bipyramids that share  a cornercorner with one Mg(1)F6 octahedra and  an edgeedge with one Mg(1)F6 octahedra. The corner-sharing octahedral tilt angles are 50°. In the second Mn site, Mn(2) is bonded in a distorted hexagonal planar geometry to two equivalent O(1), one F(1), one F(2), one F(3), and one F(4) atom. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Mn(2) and one O(1) atom. In the second O site, O(2) is bonded in a distorted water-like geometry to one Mn(1) and one O(2) atom. There are four inequivalent F sites. In the first F site, F(1) is bonded in a linear geometry to one Mn(1) and one Mn(2) atom. In the second F site, F(2) is bonded in a T-shaped geometry to one Mg(1), one Mn(1), and one Mn(2) atom. In the third F site, F(3) is bonded in a 3-coordinate geometry to one Mg(1), one Mn(1), and one Mn(2) atom. In the fourth F site, F(4) is bonded in a distorted T-shaped geometry to one Mg(1), one Mn(1), and one Mn(2) atom.
MgMn4(OF2)4 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent F(2), two equivalent F(3), and two equivalent F(4) atoms to form MgF6 octahedra that share corners with two equivalent Mn(1)OF4 trigonal bipyramids and edges with two equivalent Mn(1)OF4 trigonal bipyramids. Both Mg(1)-F(2) bond lengths are 1.97 Å. Both Mg(1)-F(3) bond lengths are 2.03 Å. Both Mg(1)-F(4) bond lengths are 1.98 Å. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(2), one F(1), one F(2), one F(3), and one F(4) atom to form MnOF4 trigonal bipyramids that share  a cornercorner with one Mg(1)F6 octahedra and  an edgeedge with one Mg(1)F6 octahedra. The corner-sharing octahedral tilt angles are 50°. The Mn(1)-O(2) bond length is 2.10 Å. The Mn(1)-F(1) bond length is 2.01 Å. The Mn(1)-F(2) bond length is 2.16 Å. The Mn(1)-F(3) bond length is 2.07 Å. The Mn(1)-F(4) bond length is 2.21 Å. In the second Mn site, Mn(2) is bonded in a distorted hexagonal planar geometry to two equivalent O(1), one F(1), one F(2), one F(3), and one F(4) atom. There is one shorter (2.10 Å) and one longer (2.30 Å) Mn(2)-O(1) bond length. The Mn(2)-F(1) bond length is 2.01 Å. The Mn(2)-F(2) bond length is 2.19 Å. The Mn(2)-F(3) bond length is 2.29 Å. The Mn(2)-F(4) bond length is 2.26 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to two equivalent Mn(2) and one O(1) atom. The O(1)-O(1) bond length is 1.41 Å. In the second O site, O(2) is bonded in a distorted water-like geometry to one Mn(1) and one O(2) atom. The O(2)-O(2) bond length is 1.33 Å. There are four inequivalent F sites. In the first F site, F(1) is bonded in a linear geometry to one Mn(1) and one Mn(2) atom. In the second F site, F(2) is bonded in a T-shaped geometry to one Mg(1), one Mn(1), and one Mn(2) atom. In the third F site, F(3) is bonded in a 3-coordinate geometry to one Mg(1), one Mn(1), and one Mn(2) atom. In the fourth F site, F(4) is bonded in a distorted T-shaped geometry to one Mg(1), one Mn(1), and one Mn(2) atom.