MgCo6O7F5 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(7), one F(1), one F(3), and one F(5) atom to form MgO3F3 octahedra that share corners with two equivalent Co(1)O3F3 octahedra, corners with two equivalent Co(3)O3F3 octahedra, and faces with two equivalent Co(2)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 35-48°. There are six inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(3), one O(6), one O(7), one F(1), one F(2), and one F(4) atom to form CoO3F3 octahedra that share corners with two equivalent Mg(1)O3F3 octahedra, corners with four equivalent Co(5)O4F2 octahedra,  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 35-48°. In the second Co site, Co(2) is bonded to one O(1), one O(2), one O(7), one F(1), one F(3), and one F(5) atom to form CoO3F3 octahedra that share  an edgeedge with one Co(1)O3F3 octahedra,  an edgeedge with one Co(3)O3F3 octahedra, and faces with two equivalent Mg(1)O3F3 octahedra. In the third Co site, Co(3) is bonded to one O(1), one O(4), one O(5), one F(2), one F(4), and one F(5) atom to form CoO3F3 octahedra that share corners with two equivalent Mg(1)O3F3 octahedra, corners with four equivalent Co(5)O4F2 octahedra,  an edgeedge with one Co(1)O3F3 octahedra, and  an edgeedge with one Co(2)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 46-49°. In the fourth Co site, Co(4) is bonded in a 5-coordinate geometry to one O(2), one O(3), one O(6), one O(7), and one F(3) atom. In the fifth Co site, Co(5) is bonded to one O(3), one O(4), one O(5), one O(6), one F(2), and one F(4) atom to form distorted corner-sharing CoO4F2 octahedra. The corner-sharing octahedral tilt angles range from 42-49°. In the sixth Co site, Co(6) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(4), one O(5), one F(3), and one F(5) atom. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted see-saw-like geometry to one Mg(1), one Co(2), one Co(3), and one Co(6) atom. In the second O site, O(2) is bonded in a trigonal pyramidal geometry to one Mg(1), one Co(2), one Co(4), and one Co(6) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(4), and one Co(5) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar 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(3), one Co(5), and one Co(6) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Co(1), one Co(4), and one Co(5) atom. In the seventh O site, O(7) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Co(1), one Co(2), and one Co(4) atom. There are five inequivalent F sites. In the first F site, F(1) is bonded in a distorted T-shaped geometry to one Mg(1), one Co(1), and one Co(2) atom. In the second F site, F(2) is bonded in a distorted T-shaped geometry to one Co(1), one Co(3), and one Co(5) atom. In the third F site, F(3) is bonded in a 4-coordinate geometry to one Mg(1), one Co(2), one Co(4), and one Co(6) atom. In the fourth F site, F(4) is bonded in a 3-coordinate geometry to one Co(1), one Co(3), and one Co(5) atom. In the fifth F site, F(5) is bonded in a 4-coordinate geometry to one Mg(1), one Co(2), one Co(3), and one Co(6) atom.
MgCo6O7F5 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(7), one F(1), one F(3), and one F(5) atom to form MgO3F3 octahedra that share corners with two equivalent Co(1)O3F3 octahedra, corners with two equivalent Co(3)O3F3 octahedra, and faces with two equivalent Co(2)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 35-48°. The Mg(1)-O(1) bond length is 2.08 Å. The Mg(1)-O(2) bond length is 1.98 Å. The Mg(1)-O(7) bond length is 2.07 Å. The Mg(1)-F(1) bond length is 2.01 Å. The Mg(1)-F(3) bond length is 1.95 Å. The Mg(1)-F(5) bond length is 2.01 Å. There are six inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(3), one O(6), one O(7), one F(1), one F(2), and one F(4) atom to form CoO3F3 octahedra that share corners with two equivalent Mg(1)O3F3 octahedra, corners with four equivalent Co(5)O4F2 octahedra,  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 35-48°. The Co(1)-O(3) bond length is 1.97 Å. The Co(1)-O(6) bond length is 1.93 Å. The Co(1)-O(7) bond length is 2.02 Å. The Co(1)-F(1) bond length is 2.09 Å. The Co(1)-F(2) bond length is 2.09 Å. The Co(1)-F(4) bond length is 1.96 Å. In the second Co site, Co(2) is bonded to one O(1), one O(2), one O(7), one F(1), one F(3), and one F(5) atom to form CoO3F3 octahedra that share  an edgeedge with one Co(1)O3F3 octahedra,  an edgeedge with one Co(3)O3F3 octahedra, and faces with two equivalent Mg(1)O3F3 octahedra. The Co(2)-O(1) bond length is 1.89 Å. The Co(2)-O(2) bond length is 1.90 Å. The Co(2)-O(7) bond length is 1.92 Å. The Co(2)-F(1) bond length is 2.03 Å. The Co(2)-F(3) bond length is 2.08 Å. The Co(2)-F(5) bond length is 2.12 Å. In the third Co site, Co(3) is bonded to one O(1), one O(4), one O(5), one F(2), one F(4), and one F(5) atom to form CoO3F3 octahedra that share corners with two equivalent Mg(1)O3F3 octahedra, corners with four equivalent Co(5)O4F2 octahedra,  an edgeedge with one Co(1)O3F3 octahedra, and  an edgeedge with one Co(2)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 46-49°. The Co(3)-O(1) bond length is 2.05 Å. The Co(3)-O(4) bond length is 2.03 Å. The Co(3)-O(5) bond length is 2.05 Å. The Co(3)-F(2) bond length is 2.05 Å. The Co(3)-F(4) bond length is 2.07 Å. The Co(3)-F(5) bond length is 2.16 Å. In the fourth Co site, Co(4) is bonded in a 5-coordinate geometry to one O(2), one O(3), one O(6), one O(7), and one F(3) atom. The Co(4)-O(2) bond length is 2.01 Å. The Co(4)-O(3) bond length is 1.92 Å. The Co(4)-O(6) bond length is 1.97 Å. The Co(4)-O(7) bond length is 1.99 Å. The Co(4)-F(3) bond length is 2.52 Å. In the fifth Co site, Co(5) is bonded to one O(3), one O(4), one O(5), one O(6), one F(2), and one F(4) atom to form distorted corner-sharing CoO4F2 octahedra. The corner-sharing octahedral tilt angles range from 42-49°. The Co(5)-O(3) bond length is 1.86 Å. The Co(5)-O(4) bond length is 1.84 Å. The Co(5)-O(5) bond length is 1.85 Å. The Co(5)-O(6) bond length is 1.90 Å. The Co(5)-F(2) bond length is 2.15 Å. The Co(5)-F(4) bond length is 2.50 Å. In the sixth Co site, Co(6) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(4), one O(5), one F(3), and one F(5) atom. The Co(6)-O(1) bond length is 2.00 Å. The Co(6)-O(2) bond length is 1.94 Å. The Co(6)-O(4) bond length is 1.83 Å. The Co(6)-O(5) bond length is 1.82 Å. The Co(6)-F(3) bond length is 2.02 Å. The Co(6)-F(5) bond length is 2.55 Å. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted see-saw-like geometry to one Mg(1), one Co(2), one Co(3), and one Co(6) atom. In the second O site, O(2) is bonded in a trigonal pyramidal geometry to one Mg(1), one Co(2), one Co(4), and one Co(6) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(4), and one Co(5) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar 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(3), one Co(5), and one Co(6) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Co(1), one Co(4), and one Co(5) atom. In the seventh O site, O(7) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Co(1), one Co(2), and one Co(4) atom. There are five inequivalent F sites. In the first F site, F(1) is bonded in a distorted T-shaped geometry to one Mg(1), one Co(1), and one Co(2) atom. In the second F site, F(2) is bonded in a distorted T-shaped geometry to one Co(1), one Co(3), and one Co(5) atom. In the third F site, F(3) is bonded in a 4-coordinate geometry to one Mg(1), one Co(2), one Co(4), and one Co(6) atom. In the fourth F site, F(4) is bonded in a 3-coordinate geometry to one Co(1), one Co(3), and one Co(5) atom. In the fifth F site, F(5) is bonded in a 4-coordinate geometry to one Mg(1), one Co(2), one Co(3), and one Co(6) atom.