MgCu6OF11 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 5-coordinate geometry to one O(1), one F(2), one F(4), one F(6), and one F(7) atom. There are six inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one F(1), one F(10), one F(11), one F(2), one F(3), and one F(9) atom to form CuF6 octahedra that share corners with two equivalent Cu(4)OF5 octahedra, corners with four equivalent Cu(2)OF5 octahedra, corners with two equivalent Cu(5)F5 square pyramids, and  an edgeedge with one Cu(6)F6 octahedra. The corner-sharing octahedral tilt angles range from 37-54°. In the second Cu site, Cu(2) is bonded to one O(1), one F(1), one F(11), one F(3), one F(8), and one F(9) atom to form distorted CuOF5 octahedra that share corners with two equivalent Cu(6)F6 octahedra, corners with four equivalent Cu(1)F6 octahedra,  an edgeedge with one Cu(4)OF5 octahedra, and  an edgeedge with one Cu(5)F5 square pyramid. The corner-sharing octahedral tilt angles range from 37-53°. In the third Cu site, Cu(3) is bonded in a 4-coordinate geometry to one O(1), one F(1), one F(3), and one F(5) atom. In the fourth Cu site, Cu(4) is bonded to one O(1), one F(2), one F(3), one F(4), one F(5), and one F(7) atom to form distorted CuOF5 octahedra that share corners with two equivalent Cu(1)F6 octahedra, corners with two equivalent Cu(6)F6 octahedra,  a cornercorner with one Cu(5)F5 square pyramid, and  an edgeedge with one Cu(2)OF5 octahedra. The corner-sharing octahedral tilt angles range from 46-68°. In the fifth Cu site, Cu(5) is bonded to one F(10), one F(6), one F(7), one F(8), and one F(9) atom to form distorted CuF5 square pyramids that share  a cornercorner with one Cu(4)OF5 octahedra, corners with two equivalent Cu(1)F6 octahedra, corners with four equivalent Cu(6)F6 octahedra, and  an edgeedge with one Cu(2)OF5 octahedra. The corner-sharing octahedral tilt angles range from 32-66°. In the sixth Cu site, Cu(6) is bonded to one F(10), one F(11), one F(5), one F(6), one F(7), and one F(8) atom to form CuF6 octahedra that share corners with two equivalent Cu(2)OF5 octahedra, corners with two equivalent Cu(4)OF5 octahedra, corners with four equivalent Cu(5)F5 square pyramids, and  an edgeedge with one Cu(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 46-68°. O(1) is bonded in a tetrahedral geometry to one Mg(1), one Cu(2), one Cu(3), and one Cu(4) atom. There are eleven inequivalent F sites. In the first F site, F(1) is bonded in a 3-coordinate geometry to one Cu(1), one Cu(2), and one Cu(3) atom. In the second F site, F(2) is bonded in a 3-coordinate geometry to one Mg(1), one Cu(1), and one Cu(4) atom. In the third F site, F(3) is bonded in a 4-coordinate geometry to one Cu(1), one Cu(2), one Cu(3), and one Cu(4) atom. In the fourth F site, F(4) is bonded in a distorted L-shaped geometry to one Mg(1) and one Cu(4) atom. In the fifth F site, F(5) is bonded in a 3-coordinate geometry to one Cu(3), one Cu(4), and one Cu(6) atom. In the sixth F site, F(6) is bonded in a distorted T-shaped geometry to one Mg(1), one Cu(5), and one Cu(6) atom. In the seventh F site, F(7) is bonded in a 4-coordinate geometry to one Mg(1), one Cu(4), one Cu(5), and one Cu(6) atom. In the eighth F site, F(8) is bonded in a distorted trigonal planar geometry to one Cu(2), one Cu(5), and one Cu(6) atom. In the ninth F site, F(9) is bonded in a trigonal planar geometry to one Cu(1), one Cu(2), and one Cu(5) atom. In the tenth F site, F(10) is bonded in a 3-coordinate geometry to one Cu(1), one Cu(5), and one Cu(6) atom. In the eleventh F site, F(11) is bonded in a distorted trigonal planar geometry to one Cu(1), one Cu(2), and one Cu(6) atom.
MgCu6OF11 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 5-coordinate geometry to one O(1), one F(2), one F(4), one F(6), and one F(7) atom. The Mg(1)-O(1) bond length is 2.04 Å. The Mg(1)-F(2) bond length is 1.92 Å. The Mg(1)-F(4) bond length is 1.98 Å. The Mg(1)-F(6) bond length is 1.95 Å. The Mg(1)-F(7) bond length is 2.22 Å. There are six inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one F(1), one F(10), one F(11), one F(2), one F(3), and one F(9) atom to form CuF6 octahedra that share corners with two equivalent Cu(4)OF5 octahedra, corners with four equivalent Cu(2)OF5 octahedra, corners with two equivalent Cu(5)F5 square pyramids, and  an edgeedge with one Cu(6)F6 octahedra. The corner-sharing octahedral tilt angles range from 37-54°. The Cu(1)-F(1) bond length is 1.93 Å. The Cu(1)-F(10) bond length is 2.43 Å. The Cu(1)-F(11) bond length is 1.94 Å. The Cu(1)-F(2) bond length is 2.40 Å. The Cu(1)-F(3) bond length is 1.92 Å. The Cu(1)-F(9) bond length is 1.91 Å. In the second Cu site, Cu(2) is bonded to one O(1), one F(1), one F(11), one F(3), one F(8), and one F(9) atom to form distorted CuOF5 octahedra that share corners with two equivalent Cu(6)F6 octahedra, corners with four equivalent Cu(1)F6 octahedra,  an edgeedge with one Cu(4)OF5 octahedra, and  an edgeedge with one Cu(5)F5 square pyramid. The corner-sharing octahedral tilt angles range from 37-53°. The Cu(2)-O(1) bond length is 2.02 Å. The Cu(2)-F(1) bond length is 2.38 Å. The Cu(2)-F(11) bond length is 2.16 Å. The Cu(2)-F(3) bond length is 1.93 Å. The Cu(2)-F(8) bond length is 2.40 Å. The Cu(2)-F(9) bond length is 1.92 Å. In the third Cu site, Cu(3) is bonded in a 4-coordinate geometry to one O(1), one F(1), one F(3), and one F(5) atom. The Cu(3)-O(1) bond length is 1.95 Å. The Cu(3)-F(1) bond length is 1.93 Å. The Cu(3)-F(3) bond length is 2.37 Å. The Cu(3)-F(5) bond length is 1.96 Å. In the fourth Cu site, Cu(4) is bonded to one O(1), one F(2), one F(3), one F(4), one F(5), and one F(7) atom to form distorted CuOF5 octahedra that share corners with two equivalent Cu(1)F6 octahedra, corners with two equivalent Cu(6)F6 octahedra,  a cornercorner with one Cu(5)F5 square pyramid, and  an edgeedge with one Cu(2)OF5 octahedra. The corner-sharing octahedral tilt angles range from 46-68°. The Cu(4)-O(1) bond length is 1.94 Å. The Cu(4)-F(2) bond length is 1.97 Å. The Cu(4)-F(3) bond length is 2.37 Å. The Cu(4)-F(4) bond length is 2.07 Å. The Cu(4)-F(5) bond length is 1.96 Å. The Cu(4)-F(7) bond length is 2.49 Å. In the fifth Cu site, Cu(5) is bonded to one F(10), one F(6), one F(7), one F(8), and one F(9) atom to form distorted CuF5 square pyramids that share  a cornercorner with one Cu(4)OF5 octahedra, corners with two equivalent Cu(1)F6 octahedra, corners with four equivalent Cu(6)F6 octahedra, and  an edgeedge with one Cu(2)OF5 octahedra. The corner-sharing octahedral tilt angles range from 32-66°. The Cu(5)-F(10) bond length is 1.91 Å. The Cu(5)-F(6) bond length is 2.09 Å. The Cu(5)-F(7) bond length is 2.01 Å. The Cu(5)-F(8) bond length is 1.93 Å. The Cu(5)-F(9) bond length is 2.19 Å. In the sixth Cu site, Cu(6) is bonded to one F(10), one F(11), one F(5), one F(6), one F(7), and one F(8) atom to form CuF6 octahedra that share corners with two equivalent Cu(2)OF5 octahedra, corners with two equivalent Cu(4)OF5 octahedra, corners with four equivalent Cu(5)F5 square pyramids, and  an edgeedge with one Cu(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 46-68°. The Cu(6)-F(10) bond length is 2.03 Å. The Cu(6)-F(11) bond length is 2.18 Å. The Cu(6)-F(5) bond length is 2.30 Å. The Cu(6)-F(6) bond length is 2.19 Å. The Cu(6)-F(7) bond length is 2.01 Å. The Cu(6)-F(8) bond length is 1.96 Å. O(1) is bonded in a tetrahedral geometry to one Mg(1), one Cu(2), one Cu(3), and one Cu(4) atom. There are eleven inequivalent F sites. In the first F site, F(1) is bonded in a 3-coordinate geometry to one Cu(1), one Cu(2), and one Cu(3) atom. In the second F site, F(2) is bonded in a 3-coordinate geometry to one Mg(1), one Cu(1), and one Cu(4) atom. In the third F site, F(3) is bonded in a 4-coordinate geometry to one Cu(1), one Cu(2), one Cu(3), and one Cu(4) atom. In the fourth F site, F(4) is bonded in a distorted L-shaped geometry to one Mg(1) and one Cu(4) atom. In the fifth F site, F(5) is bonded in a 3-coordinate geometry to one Cu(3), one Cu(4), and one Cu(6) atom. In the sixth F site, F(6) is bonded in a distorted T-shaped geometry to one Mg(1), one Cu(5), and one Cu(6) atom. In the seventh F site, F(7) is bonded in a 4-coordinate geometry to one Mg(1), one Cu(4), one Cu(5), and one Cu(6) atom. In the eighth F site, F(8) is bonded in a distorted trigonal planar geometry to one Cu(2), one Cu(5), and one Cu(6) atom. In the ninth F site, F(9) is bonded in a trigonal planar geometry to one Cu(1), one Cu(2), and one Cu(5) atom. In the tenth F site, F(10) is bonded in a 3-coordinate geometry to one Cu(1), one Cu(5), and one Cu(6) atom. In the eleventh F site, F(11) is bonded in a distorted trigonal planar geometry to one Cu(1), one Cu(2), and one Cu(6) atom.