MgV5CuO12 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(11), one O(4), one O(7), and one O(8) atom. There are five inequivalent V sites. In the first V site, V(1) is bonded to one O(1), one O(10), one O(11), one O(12), one O(3), and one O(8) atom to form VO6 octahedra that share  a cornercorner with one V(2)O4 tetrahedra,  a cornercorner with one V(4)O4 tetrahedra, corners with two equivalent V(3)O4 tetrahedra, corners with two equivalent V(5)O4 tetrahedra, and edges with two equivalent Cu(1)O6 octahedra. In the second V site, V(2) is bonded to one O(1), one O(2), one O(4), and one O(6) atom to form VO4 tetrahedra that share  a cornercorner with one V(1)O6 octahedra, corners with two equivalent Cu(1)O6 octahedra, and corners with two equivalent V(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 36-65°. In the third V site, V(3) is bonded to one O(3), one O(4), one O(6), and one O(8) atom to form VO4 tetrahedra that share  a cornercorner with one Cu(1)O6 octahedra, corners with two equivalent V(1)O6 octahedra, and corners with two equivalent V(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 25-66°. In the fourth V site, V(4) is bonded to one O(10), one O(5), one O(7), and one O(9) atom to form VO4 tetrahedra that share  a cornercorner with one V(1)O6 octahedra, corners with two equivalent Cu(1)O6 octahedra, and corners with two equivalent V(5)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 36-65°. In the fifth V site, V(5) is bonded to one O(11), one O(12), one O(7), and one O(9) atom to form VO4 tetrahedra that share  a cornercorner with one Cu(1)O6 octahedra, corners with two equivalent V(1)O6 octahedra, and corners with two equivalent V(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 26-67°. Cu(1) is bonded to one O(1), one O(10), one O(12), one O(2), one O(3), and one O(5) atom to form distorted CuO6 octahedra that share  a cornercorner with one V(3)O4 tetrahedra,  a cornercorner with one V(5)O4 tetrahedra, corners with two equivalent V(2)O4 tetrahedra, corners with two equivalent V(4)O4 tetrahedra, and edges with two equivalent V(1)O6 octahedra. There are twelve inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one V(1), one V(2), and one Cu(1) atom to form a mixture of distorted corner and edge-sharing OMgV2Cu trigonal pyramids. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one V(2) and one Cu(1) atom. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one V(1), one V(3), and one Cu(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Mg(1), one V(2), and one V(3) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one V(4) and one Cu(1) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one V(2) and one V(3) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Mg(1), one V(4), and one V(5) atom. In the eighth O site, O(8) is bonded in a distorted T-shaped geometry to one Mg(1), one V(1), and one V(3) atom. In the ninth O site, O(9) is bonded in a bent 150 degrees geometry to one V(4) and one V(5) atom. In the tenth O site, O(10) is bonded to one Mg(1), one V(1), one V(4), and one Cu(1) atom to form a mixture of distorted corner and edge-sharing OMgV2Cu trigonal pyramids. In the eleventh O site, O(11) is bonded in a distorted T-shaped geometry to one Mg(1), one V(1), and one V(5) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal non-coplanar geometry to one V(1), one V(5), and one Cu(1) atom.
MgV5CuO12 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(11), one O(4), one O(7), and one O(8) atom. The Mg(1)-O(1) bond length is 2.06 Å. The Mg(1)-O(10) bond length is 2.06 Å. The Mg(1)-O(11) bond length is 2.25 Å. The Mg(1)-O(4) bond length is 2.19 Å. The Mg(1)-O(7) bond length is 2.22 Å. The Mg(1)-O(8) bond length is 2.31 Å. There are five inequivalent V sites. In the first V site, V(1) is bonded to one O(1), one O(10), one O(11), one O(12), one O(3), and one O(8) atom to form VO6 octahedra that share  a cornercorner with one V(2)O4 tetrahedra,  a cornercorner with one V(4)O4 tetrahedra, corners with two equivalent V(3)O4 tetrahedra, corners with two equivalent V(5)O4 tetrahedra, and edges with two equivalent Cu(1)O6 octahedra. The V(1)-O(1) bond length is 2.02 Å. The V(1)-O(10) bond length is 2.02 Å. The V(1)-O(11) bond length is 2.09 Å. The V(1)-O(12) bond length is 2.05 Å. The V(1)-O(3) bond length is 2.05 Å. The V(1)-O(8) bond length is 2.08 Å. In the second V site, V(2) is bonded to one O(1), one O(2), one O(4), and one O(6) atom to form VO4 tetrahedra that share  a cornercorner with one V(1)O6 octahedra, corners with two equivalent Cu(1)O6 octahedra, and corners with two equivalent V(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 36-65°. The V(2)-O(1) bond length is 1.88 Å. The V(2)-O(2) bond length is 1.69 Å. The V(2)-O(4) bond length is 1.93 Å. The V(2)-O(6) bond length is 1.86 Å. In the third V site, V(3) is bonded to one O(3), one O(4), one O(6), and one O(8) atom to form VO4 tetrahedra that share  a cornercorner with one Cu(1)O6 octahedra, corners with two equivalent V(1)O6 octahedra, and corners with two equivalent V(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 25-66°. The V(3)-O(3) bond length is 1.73 Å. The V(3)-O(4) bond length is 1.80 Å. The V(3)-O(6) bond length is 1.76 Å. The V(3)-O(8) bond length is 1.74 Å. In the fourth V site, V(4) is bonded to one O(10), one O(5), one O(7), and one O(9) atom to form VO4 tetrahedra that share  a cornercorner with one V(1)O6 octahedra, corners with two equivalent Cu(1)O6 octahedra, and corners with two equivalent V(5)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 36-65°. The V(4)-O(10) bond length is 1.89 Å. The V(4)-O(5) bond length is 1.69 Å. The V(4)-O(7) bond length is 1.93 Å. The V(4)-O(9) bond length is 1.86 Å. In the fifth V site, V(5) is bonded to one O(11), one O(12), one O(7), and one O(9) atom to form VO4 tetrahedra that share  a cornercorner with one Cu(1)O6 octahedra, corners with two equivalent V(1)O6 octahedra, and corners with two equivalent V(4)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 26-67°. The V(5)-O(11) bond length is 1.75 Å. The V(5)-O(12) bond length is 1.73 Å. The V(5)-O(7) bond length is 1.80 Å. The V(5)-O(9) bond length is 1.76 Å. Cu(1) is bonded to one O(1), one O(10), one O(12), one O(2), one O(3), and one O(5) atom to form distorted CuO6 octahedra that share  a cornercorner with one V(3)O4 tetrahedra,  a cornercorner with one V(5)O4 tetrahedra, corners with two equivalent V(2)O4 tetrahedra, corners with two equivalent V(4)O4 tetrahedra, and edges with two equivalent V(1)O6 octahedra. The Cu(1)-O(1) bond length is 2.42 Å. The Cu(1)-O(10) bond length is 2.37 Å. The Cu(1)-O(12) bond length is 2.30 Å. The Cu(1)-O(2) bond length is 1.96 Å. The Cu(1)-O(3) bond length is 2.26 Å. The Cu(1)-O(5) bond length is 1.96 Å. There are twelve inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one V(1), one V(2), and one Cu(1) atom to form a mixture of distorted corner and edge-sharing OMgV2Cu trigonal pyramids. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one V(2) and one Cu(1) atom. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one V(1), one V(3), and one Cu(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Mg(1), one V(2), and one V(3) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one V(4) and one Cu(1) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one V(2) and one V(3) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Mg(1), one V(4), and one V(5) atom. In the eighth O site, O(8) is bonded in a distorted T-shaped geometry to one Mg(1), one V(1), and one V(3) atom. In the ninth O site, O(9) is bonded in a bent 150 degrees geometry to one V(4) and one V(5) atom. In the tenth O site, O(10) is bonded to one Mg(1), one V(1), one V(4), and one Cu(1) atom to form a mixture of distorted corner and edge-sharing OMgV2Cu trigonal pyramids. In the eleventh O site, O(11) is bonded in a distorted T-shaped geometry to one Mg(1), one V(1), and one V(5) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal non-coplanar geometry to one V(1), one V(5), and one Cu(1) atom.