MgCo6(OF)6 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 5-coordinate geometry to one O(2), one O(3), one F(3), one F(4), and one F(6) atom. There are six inequivalent Co sites. In the first Co site, Co(1) is bonded in a 5-coordinate geometry to one O(1), one O(5), one O(6), one F(1), and one F(5) atom. In the second Co site, Co(2) is bonded to one O(2), one O(3), one O(6), one F(1), one F(4), and one F(6) atom to form distorted CoO3F3 octahedra that share corners with four equivalent Co(4)O3F3 octahedra,  a cornercorner with one Co(6)O3F tetrahedra,  an edgeedge with one Co(3)O3F3 octahedra, and  an edgeedge with one Co(6)O3F tetrahedra. The corner-sharing octahedral tilt angles range from 47-53°. In the third Co site, Co(3) is bonded to one O(1), one O(2), one O(4), one F(3), one F(5), and one F(6) atom to form distorted CoO3F3 octahedra that share corners with three equivalent Co(5)O3F2 square pyramids,  a cornercorner with one Co(6)O3F tetrahedra,  an edgeedge with one Co(2)O3F3 octahedra, and  an edgeedge with one Co(6)O3F tetrahedra. In the fourth Co site, Co(4) is bonded to one O(3), one O(5), one O(6), one F(1), one F(2), and one F(4) atom to form CoO3F3 octahedra that share corners with four equivalent Co(2)O3F3 octahedra,  a cornercorner with one Co(6)O3F tetrahedra, and  an edgeedge with one Co(5)O3F2 square pyramid. The corner-sharing octahedral tilt angles range from 47-53°. In the fifth Co site, Co(5) is bonded to one O(1), one O(4), one O(5), one F(2), and one F(5) atom to form distorted CoO3F2 square pyramids that share corners with three equivalent Co(3)O3F3 octahedra,  a cornercorner with one Co(6)O3F tetrahedra, and  an edgeedge with one Co(4)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 44-53°. In the sixth Co site, Co(6) is bonded to one O(2), one O(3), one O(4), and one F(6) atom to form CoO3F tetrahedra that share  a cornercorner with one Co(2)O3F3 octahedra,  a cornercorner with one Co(3)O3F3 octahedra,  a cornercorner with one Co(4)O3F3 octahedra,  a cornercorner with one Co(5)O3F2 square pyramid,  an edgeedge with one Co(2)O3F3 octahedra, and  an edgeedge with one Co(3)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 59-72°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(3), and one Co(5) atom. In the second O site, O(2) is bonded in a tetrahedral geometry to one Mg(1), one Co(2), one Co(3), and one Co(6) atom. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Co(2), one Co(4), and one Co(6) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Co(3), one Co(5), and one Co(6) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(4), and one Co(5) atom. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Co(1), one Co(2), and one Co(4) atom. There are six inequivalent F sites. In the first F site, F(1) is bonded in a distorted T-shaped geometry to one Co(1), one Co(2), and one Co(4) atom. In the second F site, F(2) is bonded in a distorted L-shaped geometry to one Co(4) and one Co(5) atom. In the third F site, F(3) is bonded in a water-like geometry to one Mg(1) and one Co(3) atom. In the fourth F site, F(4) is bonded in a 3-coordinate geometry to one Mg(1), one Co(2), and one Co(4) atom. In the fifth F site, F(5) is bonded in a distorted T-shaped geometry to one Co(1), one Co(3), and one Co(5) atom. In the sixth F site, F(6) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Co(2), one Co(3), and one Co(6) atom.
MgCo6(OF)6 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 5-coordinate geometry to one O(2), one O(3), one F(3), one F(4), and one F(6) atom. The Mg(1)-O(2) bond length is 1.96 Å. The Mg(1)-O(3) bond length is 2.10 Å. The Mg(1)-F(3) bond length is 1.97 Å. The Mg(1)-F(4) bond length is 1.98 Å. The Mg(1)-F(6) bond length is 1.93 Å. There are six inequivalent Co sites. In the first Co site, Co(1) is bonded in a 5-coordinate geometry to one O(1), one O(5), one O(6), one F(1), and one F(5) atom. The Co(1)-O(1) bond length is 2.01 Å. The Co(1)-O(5) bond length is 1.78 Å. The Co(1)-O(6) bond length is 1.93 Å. The Co(1)-F(1) bond length is 2.06 Å. The Co(1)-F(5) bond length is 2.09 Å. In the second Co site, Co(2) is bonded to one O(2), one O(3), one O(6), one F(1), one F(4), and one F(6) atom to form distorted CoO3F3 octahedra that share corners with four equivalent Co(4)O3F3 octahedra,  a cornercorner with one Co(6)O3F tetrahedra,  an edgeedge with one Co(3)O3F3 octahedra, and  an edgeedge with one Co(6)O3F tetrahedra. The corner-sharing octahedral tilt angles range from 47-53°. The Co(2)-O(2) bond length is 1.94 Å. The Co(2)-O(3) bond length is 1.88 Å. The Co(2)-O(6) bond length is 1.80 Å. The Co(2)-F(1) bond length is 2.05 Å. The Co(2)-F(4) bond length is 2.08 Å. The Co(2)-F(6) bond length is 2.41 Å. In the third Co site, Co(3) is bonded to one O(1), one O(2), one O(4), one F(3), one F(5), and one F(6) atom to form distorted CoO3F3 octahedra that share corners with three equivalent Co(5)O3F2 square pyramids,  a cornercorner with one Co(6)O3F tetrahedra,  an edgeedge with one Co(2)O3F3 octahedra, and  an edgeedge with one Co(6)O3F tetrahedra. The Co(3)-O(1) bond length is 1.86 Å. The Co(3)-O(2) bond length is 2.03 Å. The Co(3)-O(4) bond length is 1.87 Å. The Co(3)-F(3) bond length is 2.00 Å. The Co(3)-F(5) bond length is 2.06 Å. The Co(3)-F(6) bond length is 2.33 Å. In the fourth Co site, Co(4) is bonded to one O(3), one O(5), one O(6), one F(1), one F(2), and one F(4) atom to form CoO3F3 octahedra that share corners with four equivalent Co(2)O3F3 octahedra,  a cornercorner with one Co(6)O3F tetrahedra, and  an edgeedge with one Co(5)O3F2 square pyramid. The corner-sharing octahedral tilt angles range from 47-53°. The Co(4)-O(3) bond length is 2.10 Å. The Co(4)-O(5) bond length is 2.13 Å. The Co(4)-O(6) bond length is 2.02 Å. The Co(4)-F(1) bond length is 2.10 Å. The Co(4)-F(2) bond length is 2.04 Å. The Co(4)-F(4) bond length is 2.28 Å. In the fifth Co site, Co(5) is bonded to one O(1), one O(4), one O(5), one F(2), and one F(5) atom to form distorted CoO3F2 square pyramids that share corners with three equivalent Co(3)O3F3 octahedra,  a cornercorner with one Co(6)O3F tetrahedra, and  an edgeedge with one Co(4)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 44-53°. The Co(5)-O(1) bond length is 1.90 Å. The Co(5)-O(4) bond length is 1.92 Å. The Co(5)-O(5) bond length is 1.91 Å. The Co(5)-F(2) bond length is 1.99 Å. The Co(5)-F(5) bond length is 2.12 Å. In the sixth Co site, Co(6) is bonded to one O(2), one O(3), one O(4), and one F(6) atom to form CoO3F tetrahedra that share  a cornercorner with one Co(2)O3F3 octahedra,  a cornercorner with one Co(3)O3F3 octahedra,  a cornercorner with one Co(4)O3F3 octahedra,  a cornercorner with one Co(5)O3F2 square pyramid,  an edgeedge with one Co(2)O3F3 octahedra, and  an edgeedge with one Co(3)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 59-72°. The Co(6)-O(2) bond length is 1.87 Å. The Co(6)-O(3) bond length is 1.96 Å. The Co(6)-O(4) bond length is 1.96 Å. The Co(6)-F(6) bond length is 2.01 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(3), and one Co(5) atom. In the second O site, O(2) is bonded in a tetrahedral geometry to one Mg(1), one Co(2), one Co(3), and one Co(6) atom. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Co(2), one Co(4), and one Co(6) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Co(3), one Co(5), and one Co(6) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(4), and one Co(5) atom. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Co(1), one Co(2), and one Co(4) atom. There are six inequivalent F sites. In the first F site, F(1) is bonded in a distorted T-shaped geometry to one Co(1), one Co(2), and one Co(4) atom. In the second F site, F(2) is bonded in a distorted L-shaped geometry to one Co(4) and one Co(5) atom. In the third F site, F(3) is bonded in a water-like geometry to one Mg(1) and one Co(3) atom. In the fourth F site, F(4) is bonded in a 3-coordinate geometry to one Mg(1), one Co(2), and one Co(4) atom. In the fifth F site, F(5) is bonded in a distorted T-shaped geometry to one Co(1), one Co(3), and one Co(5) atom. In the sixth F site, F(6) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Co(2), one Co(3), and one Co(6) atom.