MgCo6(O2F)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(4), one O(6), one F(1), one F(2), and one F(4) atom to form MgO3F3 octahedra that share  a cornercorner with one Co(3)O4F2 octahedra, corners with two equivalent Co(6)O3F3 octahedra,  a cornercorner with one Co(1)O4F square pyramid,  a cornercorner with one Co(4)O5 trigonal bipyramid, edges with two equivalent Co(5)O4F2 octahedra, and  a faceface with one Co(3)O4F2 octahedra. The corner-sharing octahedral tilt angles are 49°. There are six inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(2), one O(6), one O(7), one O(8), and one F(3) atom to form distorted CoO4F square pyramids that share  a cornercorner with one Mg(1)O3F3 octahedra, corners with two equivalent Co(3)O4F2 octahedra, corners with three equivalent Co(6)O3F3 octahedra,  an edgeedge with one Co(5)O4F2 octahedra, and  an edgeedge with one Co(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 40-73°. In the second Co site, Co(2) is bonded in a 6-coordinate geometry to one O(1), one O(4), one O(5), one F(1), one F(2), and one F(3) atom. In the third Co site, Co(3) is bonded to one O(2), one O(3), one O(4), one O(6), one F(1), and one F(4) atom to form distorted CoO4F2 octahedra that share  a cornercorner with one Mg(1)O3F3 octahedra, corners with three equivalent Co(5)O4F2 octahedra, corners with two equivalent Co(1)O4F square pyramids,  a cornercorner with one Co(4)O5 trigonal bipyramid,  an edgeedge with one Co(6)O3F3 octahedra, and  a faceface with one Mg(1)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 38-52°. In the fourth Co site, Co(4) is bonded to one O(1), one O(3), one O(5), one O(7), and one O(8) atom to form distorted CoO5 trigonal bipyramids that share  a cornercorner with one Mg(1)O3F3 octahedra,  a cornercorner with one Co(3)O4F2 octahedra, corners with three equivalent Co(6)O3F3 octahedra,  an edgeedge with one Co(5)O4F2 octahedra, and  an edgeedge with one Co(1)O4F square pyramid. The corner-sharing octahedral tilt angles range from 45-69°. In the fifth Co site, Co(5) is bonded to one O(1), one O(2), one O(5), one O(6), one F(2), and one F(4) atom to form CoO4F2 octahedra that share corners with two equivalent Co(6)O3F3 octahedra, corners with three equivalent Co(3)O4F2 octahedra, edges with two equivalent Mg(1)O3F3 octahedra,  an edgeedge with one Co(1)O4F square pyramid, and  an edgeedge with one Co(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 38-52°. In the sixth Co site, Co(6) is bonded to one O(3), one O(7), one O(8), one F(2), one F(3), and one F(4) atom to form CoO3F3 octahedra that share corners with two equivalent Mg(1)O3F3 octahedra, corners with two equivalent Co(5)O4F2 octahedra, corners with three equivalent Co(1)O4F square pyramids, corners with three equivalent Co(4)O5 trigonal bipyramids, and  an edgeedge with one Co(3)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 44-51°. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Co(2), one Co(4), and one Co(5) atom to form corner-sharing OMgCo3 trigonal pyramids. In the second O site, O(2) is bonded in a trigonal planar geometry to one Co(1), one Co(3), and one Co(5) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Co(3), one Co(4), and one Co(6) atom. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one Mg(1), one Co(2), and one Co(3) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Co(2), one Co(4), and one Co(5) atom. In the sixth O site, O(6) is bonded to one Mg(1), one Co(1), one Co(3), and one Co(5) atom to form corner-sharing OMgCo3 trigonal pyramids. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Co(1), one Co(4), and one Co(6) atom. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Co(1), one Co(4), and one Co(6) atom. There are four inequivalent F sites. In the first F site, F(1) is bonded in a T-shaped geometry to one Mg(1), one Co(2), and one Co(3) atom. In the second F site, F(2) is bonded in a 4-coordinate geometry to one Mg(1), one Co(2), one Co(5), and one Co(6) atom. In the third F site, F(3) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(2), and one Co(6) atom. In the fourth F site, F(4) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Co(3), one Co(5), and one Co(6) atom.
MgCo6(O2F)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(4), one O(6), one F(1), one F(2), and one F(4) atom to form MgO3F3 octahedra that share  a cornercorner with one Co(3)O4F2 octahedra, corners with two equivalent Co(6)O3F3 octahedra,  a cornercorner with one Co(1)O4F square pyramid,  a cornercorner with one Co(4)O5 trigonal bipyramid, edges with two equivalent Co(5)O4F2 octahedra, and  a faceface with one Co(3)O4F2 octahedra. The corner-sharing octahedral tilt angles are 49°. The Mg(1)-O(1) bond length is 2.02 Å. The Mg(1)-O(4) bond length is 2.05 Å. The Mg(1)-O(6) bond length is 2.05 Å. The Mg(1)-F(1) bond length is 2.02 Å. The Mg(1)-F(2) bond length is 1.99 Å. The Mg(1)-F(4) bond length is 2.00 Å. There are six inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(2), one O(6), one O(7), one O(8), and one F(3) atom to form distorted CoO4F square pyramids that share  a cornercorner with one Mg(1)O3F3 octahedra, corners with two equivalent Co(3)O4F2 octahedra, corners with three equivalent Co(6)O3F3 octahedra,  an edgeedge with one Co(5)O4F2 octahedra, and  an edgeedge with one Co(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 40-73°. The Co(1)-O(2) bond length is 1.92 Å. The Co(1)-O(6) bond length is 1.98 Å. The Co(1)-O(7) bond length is 1.93 Å. The Co(1)-O(8) bond length is 1.91 Å. The Co(1)-F(3) bond length is 1.96 Å. In the second Co site, Co(2) is bonded in a 6-coordinate geometry to one O(1), one O(4), one O(5), one F(1), one F(2), and one F(3) atom. The Co(2)-O(1) bond length is 2.01 Å. The Co(2)-O(4) bond length is 1.75 Å. The Co(2)-O(5) bond length is 1.92 Å. The Co(2)-F(1) bond length is 2.08 Å. The Co(2)-F(2) bond length is 2.53 Å. The Co(2)-F(3) bond length is 1.98 Å. In the third Co site, Co(3) is bonded to one O(2), one O(3), one O(4), one O(6), one F(1), and one F(4) atom to form distorted CoO4F2 octahedra that share  a cornercorner with one Mg(1)O3F3 octahedra, corners with three equivalent Co(5)O4F2 octahedra, corners with two equivalent Co(1)O4F square pyramids,  a cornercorner with one Co(4)O5 trigonal bipyramid,  an edgeedge with one Co(6)O3F3 octahedra, and  a faceface with one Mg(1)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 38-52°. The Co(3)-O(2) bond length is 1.87 Å. The Co(3)-O(3) bond length is 1.85 Å. The Co(3)-O(4) bond length is 1.93 Å. The Co(3)-O(6) bond length is 1.96 Å. The Co(3)-F(1) bond length is 2.09 Å. The Co(3)-F(4) bond length is 2.37 Å. In the fourth Co site, Co(4) is bonded to one O(1), one O(3), one O(5), one O(7), and one O(8) atom to form distorted CoO5 trigonal bipyramids that share  a cornercorner with one Mg(1)O3F3 octahedra,  a cornercorner with one Co(3)O4F2 octahedra, corners with three equivalent Co(6)O3F3 octahedra,  an edgeedge with one Co(5)O4F2 octahedra, and  an edgeedge with one Co(1)O4F square pyramid. The corner-sharing octahedral tilt angles range from 45-69°. The Co(4)-O(1) bond length is 1.97 Å. The Co(4)-O(3) bond length is 1.86 Å. The Co(4)-O(5) bond length is 1.89 Å. The Co(4)-O(7) bond length is 1.89 Å. The Co(4)-O(8) bond length is 1.90 Å. In the fifth Co site, Co(5) is bonded to one O(1), one O(2), one O(5), one O(6), one F(2), and one F(4) atom to form CoO4F2 octahedra that share corners with two equivalent Co(6)O3F3 octahedra, corners with three equivalent Co(3)O4F2 octahedra, edges with two equivalent Mg(1)O3F3 octahedra,  an edgeedge with one Co(1)O4F square pyramid, and  an edgeedge with one Co(4)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 38-52°. The Co(5)-O(1) bond length is 1.92 Å. The Co(5)-O(2) bond length is 1.90 Å. The Co(5)-O(5) bond length is 1.88 Å. The Co(5)-O(6) bond length is 1.94 Å. The Co(5)-F(2) bond length is 2.36 Å. The Co(5)-F(4) bond length is 2.34 Å. In the sixth Co site, Co(6) is bonded to one O(3), one O(7), one O(8), one F(2), one F(3), and one F(4) atom to form CoO3F3 octahedra that share corners with two equivalent Mg(1)O3F3 octahedra, corners with two equivalent Co(5)O4F2 octahedra, corners with three equivalent Co(1)O4F square pyramids, corners with three equivalent Co(4)O5 trigonal bipyramids, and  an edgeedge with one Co(3)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 44-51°. The Co(6)-O(3) bond length is 2.02 Å. The Co(6)-O(7) bond length is 1.95 Å. The Co(6)-O(8) bond length is 1.95 Å. The Co(6)-F(2) bond length is 2.10 Å. The Co(6)-F(3) bond length is 2.25 Å. The Co(6)-F(4) bond length is 2.19 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Co(2), one Co(4), and one Co(5) atom to form corner-sharing OMgCo3 trigonal pyramids. In the second O site, O(2) is bonded in a trigonal planar geometry to one Co(1), one Co(3), and one Co(5) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Co(3), one Co(4), and one Co(6) atom. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one Mg(1), one Co(2), and one Co(3) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Co(2), one Co(4), and one Co(5) atom. In the sixth O site, O(6) is bonded to one Mg(1), one Co(1), one Co(3), and one Co(5) atom to form corner-sharing OMgCo3 trigonal pyramids. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Co(1), one Co(4), and one Co(6) atom. In the eighth O site, O(8) is bonded in a trigonal planar geometry to one Co(1), one Co(4), and one Co(6) atom. There are four inequivalent F sites. In the first F site, F(1) is bonded in a T-shaped geometry to one Mg(1), one Co(2), and one Co(3) atom. In the second F site, F(2) is bonded in a 4-coordinate geometry to one Mg(1), one Co(2), one Co(5), and one Co(6) atom. In the third F site, F(3) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(2), and one Co(6) atom. In the fourth F site, F(4) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Co(3), one Co(5), and one Co(6) atom.