MgCo6O7F5 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(3), one F(2), one F(4), and one F(5) atom to form MgO3F3 octahedra that share  a cornercorner with one Co(4)O3F3 octahedra,  a cornercorner with one Co(6)O3F3 octahedra, corners with two equivalent Co(5)O3F3 octahedra,  a cornercorner with one Co(1)O4F trigonal bipyramid,  a cornercorner with one Co(3)O4F trigonal bipyramid,  an edgeedge with one Co(1)O4F trigonal bipyramid,  an edgeedge with one Co(3)O4F trigonal bipyramid,  a faceface with one Co(4)O3F3 octahedra, and  a faceface with one Co(6)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 38-53°. There are six inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(2), one O(3), one O(4), one O(7), and one F(2) atom to form distorted CoO4F trigonal bipyramids that share  a cornercorner with one Mg(1)O3F3 octahedra,  a cornercorner with one Co(4)O3F3 octahedra, corners with two equivalent Co(5)O3F3 octahedra, corners with three equivalent Co(6)O3F3 octahedra,  an edgeedge with one Mg(1)O3F3 octahedra,  an edgeedge with one Co(2)O4F2 octahedra, and  an edgeedge with one Co(3)O4F trigonal bipyramid. The corner-sharing octahedral tilt angles range from 43-72°. In the second Co site, Co(2) is bonded to one O(4), one O(5), one O(6), one O(7), one F(1), and one F(3) atom to form distorted CoO4F2 octahedra that share corners with two equivalent Co(4)O3F3 octahedra, corners with two equivalent Co(6)O3F3 octahedra, corners with four equivalent Co(5)O3F3 octahedra,  an edgeedge with one Co(1)O4F trigonal bipyramid, and  an edgeedge with one Co(3)O4F trigonal bipyramid. The corner-sharing octahedral tilt angles range from 43-54°. In the third Co site, Co(3) is bonded to one O(1), one O(3), one O(5), one O(6), and one F(2) atom to form distorted CoO4F trigonal bipyramids that share  a cornercorner with one Mg(1)O3F3 octahedra,  a cornercorner with one Co(5)O3F3 octahedra, corners with two equivalent Co(6)O3F3 octahedra, corners with three equivalent Co(4)O3F3 octahedra,  an edgeedge with one Mg(1)O3F3 octahedra,  an edgeedge with one Co(2)O4F2 octahedra, and  an edgeedge with one Co(1)O4F trigonal bipyramid. The corner-sharing octahedral tilt angles range from 40-74°. In the fourth Co site, Co(4) is bonded to one O(1), one O(3), one O(6), one F(1), one F(4), and one F(5) atom to form distorted CoO3F3 octahedra that share  a cornercorner with one Mg(1)O3F3 octahedra, corners with two equivalent Co(2)O4F2 octahedra,  a cornercorner with one Co(1)O4F trigonal bipyramid, corners with three equivalent Co(3)O4F trigonal bipyramids,  an edgeedge with one Co(5)O3F3 octahedra,  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 53-54°. In the fifth Co site, Co(5) is bonded to one O(2), one O(5), one O(7), one F(1), one F(3), and one F(5) atom to form CoO3F3 octahedra that share corners with two equivalent Mg(1)O3F3 octahedra, corners with four equivalent Co(2)O4F2 octahedra,  a cornercorner with one Co(3)O4F trigonal bipyramid, corners with two equivalent Co(1)O4F trigonal bipyramids,  an edgeedge with one Co(4)O3F3 octahedra, and  an edgeedge with one Co(6)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 38-48°. In the sixth Co site, Co(6) is bonded to one O(1), one O(2), one O(4), one F(2), one F(3), and one F(4) atom to form distorted CoO3F3 octahedra that share  a cornercorner with one Mg(1)O3F3 octahedra, corners with two equivalent Co(2)O4F2 octahedra, corners with two equivalent Co(3)O4F trigonal bipyramids, corners with three equivalent Co(1)O4F trigonal bipyramids,  an edgeedge with one Co(4)O3F3 octahedra,  an edgeedge with one Co(5)O3F3 octahedra, and  a faceface with one Mg(1)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 48-51°. 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(3), one Co(4), and one Co(6) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Co(1), one Co(5), and one Co(6) atom. In the third O site, O(3) is bonded to one Mg(1), one Co(1), one Co(3), and one Co(4) atom to form OMgCo3 trigonal pyramids that share  a cornercorner with one F(2)MgCo3 tetrahedra and  an edgeedge with one F(2)MgCo3 tetrahedra. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Co(1), one Co(2), and one Co(6) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Co(2), one Co(3), and one Co(5) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Co(2), one Co(3), and one Co(4) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(2), and one Co(5) atom. There are five inequivalent F sites. In the first F site, F(1) is bonded in a 3-coordinate geometry to one Co(2), one Co(4), and one Co(5) atom. In the second F site, F(2) is bonded to one Mg(1), one Co(1), one Co(3), and one Co(6) atom to form distorted FMgCo3 tetrahedra that share  a cornercorner with one O(3)MgCo3 trigonal pyramid and  an edgeedge with one O(3)MgCo3 trigonal pyramid. In the third F site, F(3) is bonded in a distorted T-shaped geometry to one Co(2), one Co(5), and one Co(6) atom. In the fourth F site, F(4) is bonded in a distorted T-shaped geometry to one Mg(1), one Co(4), and one Co(6) atom. In the fifth F site, F(5) is bonded in a T-shaped geometry to one Mg(1), one Co(4), and one Co(5) atom.
MgCo6O7F5 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(3), one F(2), one F(4), and one F(5) atom to form MgO3F3 octahedra that share  a cornercorner with one Co(4)O3F3 octahedra,  a cornercorner with one Co(6)O3F3 octahedra, corners with two equivalent Co(5)O3F3 octahedra,  a cornercorner with one Co(1)O4F trigonal bipyramid,  a cornercorner with one Co(3)O4F trigonal bipyramid,  an edgeedge with one Co(1)O4F trigonal bipyramid,  an edgeedge with one Co(3)O4F trigonal bipyramid,  a faceface with one Co(4)O3F3 octahedra, and  a faceface with one Co(6)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 38-53°. The Mg(1)-O(1) bond length is 2.13 Å. The Mg(1)-O(2) bond length is 2.12 Å. The Mg(1)-O(3) bond length is 2.04 Å. The Mg(1)-F(2) bond length is 1.95 Å. The Mg(1)-F(4) bond length is 1.98 Å. The Mg(1)-F(5) bond length is 1.99 Å. There are six inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(2), one O(3), one O(4), one O(7), and one F(2) atom to form distorted CoO4F trigonal bipyramids that share  a cornercorner with one Mg(1)O3F3 octahedra,  a cornercorner with one Co(4)O3F3 octahedra, corners with two equivalent Co(5)O3F3 octahedra, corners with three equivalent Co(6)O3F3 octahedra,  an edgeedge with one Mg(1)O3F3 octahedra,  an edgeedge with one Co(2)O4F2 octahedra, and  an edgeedge with one Co(3)O4F trigonal bipyramid. The corner-sharing octahedral tilt angles range from 43-72°. The Co(1)-O(2) bond length is 1.84 Å. The Co(1)-O(3) bond length is 2.10 Å. The Co(1)-O(4) bond length is 1.87 Å. The Co(1)-O(7) bond length is 2.06 Å. The Co(1)-F(2) bond length is 2.08 Å. In the second Co site, Co(2) is bonded to one O(4), one O(5), one O(6), one O(7), one F(1), and one F(3) atom to form distorted CoO4F2 octahedra that share corners with two equivalent Co(4)O3F3 octahedra, corners with two equivalent Co(6)O3F3 octahedra, corners with four equivalent Co(5)O3F3 octahedra,  an edgeedge with one Co(1)O4F trigonal bipyramid, and  an edgeedge with one Co(3)O4F trigonal bipyramid. The corner-sharing octahedral tilt angles range from 43-54°. The Co(2)-O(4) bond length is 1.83 Å. The Co(2)-O(5) bond length is 1.93 Å. The Co(2)-O(6) bond length is 1.89 Å. The Co(2)-O(7) bond length is 1.90 Å. The Co(2)-F(1) bond length is 2.49 Å. The Co(2)-F(3) bond length is 2.25 Å. In the third Co site, Co(3) is bonded to one O(1), one O(3), one O(5), one O(6), and one F(2) atom to form distorted CoO4F trigonal bipyramids that share  a cornercorner with one Mg(1)O3F3 octahedra,  a cornercorner with one Co(5)O3F3 octahedra, corners with two equivalent Co(6)O3F3 octahedra, corners with three equivalent Co(4)O3F3 octahedra,  an edgeedge with one Mg(1)O3F3 octahedra,  an edgeedge with one Co(2)O4F2 octahedra, and  an edgeedge with one Co(1)O4F trigonal bipyramid. The corner-sharing octahedral tilt angles range from 40-74°. The Co(3)-O(1) bond length is 1.86 Å. The Co(3)-O(3) bond length is 1.98 Å. The Co(3)-O(5) bond length is 1.92 Å. The Co(3)-O(6) bond length is 2.02 Å. The Co(3)-F(2) bond length is 2.19 Å. In the fourth Co site, Co(4) is bonded to one O(1), one O(3), one O(6), one F(1), one F(4), and one F(5) atom to form distorted CoO3F3 octahedra that share  a cornercorner with one Mg(1)O3F3 octahedra, corners with two equivalent Co(2)O4F2 octahedra,  a cornercorner with one Co(1)O4F trigonal bipyramid, corners with three equivalent Co(3)O4F trigonal bipyramids,  an edgeedge with one Co(5)O3F3 octahedra,  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 53-54°. The Co(4)-O(1) bond length is 1.94 Å. The Co(4)-O(3) bond length is 2.14 Å. The Co(4)-O(6) bond length is 1.85 Å. The Co(4)-F(1) bond length is 1.94 Å. The Co(4)-F(4) bond length is 2.13 Å. The Co(4)-F(5) bond length is 2.14 Å. In the fifth Co site, Co(5) is bonded to one O(2), one O(5), one O(7), one F(1), one F(3), and one F(5) atom to form CoO3F3 octahedra that share corners with two equivalent Mg(1)O3F3 octahedra, corners with four equivalent Co(2)O4F2 octahedra,  a cornercorner with one Co(3)O4F trigonal bipyramid, corners with two equivalent Co(1)O4F trigonal bipyramids,  an edgeedge with one Co(4)O3F3 octahedra, and  an edgeedge with one Co(6)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 38-48°. The Co(5)-O(2) bond length is 2.02 Å. The Co(5)-O(5) bond length is 1.93 Å. The Co(5)-O(7) bond length is 1.87 Å. The Co(5)-F(1) bond length is 2.07 Å. The Co(5)-F(3) bond length is 2.06 Å. The Co(5)-F(5) bond length is 2.13 Å. In the sixth Co site, Co(6) is bonded to one O(1), one O(2), one O(4), one F(2), one F(3), and one F(4) atom to form distorted CoO3F3 octahedra that share  a cornercorner with one Mg(1)O3F3 octahedra, corners with two equivalent Co(2)O4F2 octahedra, corners with two equivalent Co(3)O4F trigonal bipyramids, corners with three equivalent Co(1)O4F trigonal bipyramids,  an edgeedge with one Co(4)O3F3 octahedra,  an edgeedge with one Co(5)O3F3 octahedra, and  a faceface with one Mg(1)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 48-51°. The Co(6)-O(1) bond length is 2.17 Å. The Co(6)-O(2) bond length is 2.08 Å. The Co(6)-O(4) bond length is 1.88 Å. The Co(6)-F(2) bond length is 2.30 Å. The Co(6)-F(3) bond length is 2.03 Å. The Co(6)-F(4) bond length is 2.05 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(3), one Co(4), and one Co(6) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Co(1), one Co(5), and one Co(6) atom. In the third O site, O(3) is bonded to one Mg(1), one Co(1), one Co(3), and one Co(4) atom to form OMgCo3 trigonal pyramids that share  a cornercorner with one F(2)MgCo3 tetrahedra and  an edgeedge with one F(2)MgCo3 tetrahedra. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Co(1), one Co(2), and one Co(6) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Co(2), one Co(3), and one Co(5) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Co(2), one Co(3), and one Co(4) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Co(1), one Co(2), and one Co(5) atom. There are five inequivalent F sites. In the first F site, F(1) is bonded in a 3-coordinate geometry to one Co(2), one Co(4), and one Co(5) atom. In the second F site, F(2) is bonded to one Mg(1), one Co(1), one Co(3), and one Co(6) atom to form distorted FMgCo3 tetrahedra that share  a cornercorner with one O(3)MgCo3 trigonal pyramid and  an edgeedge with one O(3)MgCo3 trigonal pyramid. In the third F site, F(3) is bonded in a distorted T-shaped geometry to one Co(2), one Co(5), and one Co(6) atom. In the fourth F site, F(4) is bonded in a distorted T-shaped geometry to one Mg(1), one Co(4), and one Co(6) atom. In the fifth F site, F(5) is bonded in a T-shaped geometry to one Mg(1), one Co(4), and one Co(5) atom.