MgCu3(NiO3)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 9-coordinate geometry to one O(1), one O(10), one O(11), one O(12), one O(2), one O(3), one O(4), one O(7), and one O(8) atom. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(11), one O(12), one O(3), one O(6), one O(7), and one O(9) atom to form corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 42-47°. In the second Ni site, Ni(2) is bonded to one O(1), one O(10), one O(11), one O(2), one O(4), and one O(6) atom to form corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 42-48°. In the third Ni site, Ni(3) is bonded to one O(10), one O(3), one O(4), one O(5), one O(8), and one O(9) atom to form corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 42-47°. In the fourth Ni site, Ni(4) is bonded to one O(1), one O(12), one O(2), one O(5), one O(7), and one O(8) atom to form corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 43-48°. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a distorted square co-planar geometry to one O(10), one O(12), one O(4), and one O(7) atom. In the second Cu site, Cu(2) is bonded in a square co-planar geometry to one O(1), one O(2), one O(3), and one O(9) atom. In the third Cu site, Cu(3) is bonded in a square co-planar geometry to one O(11), one O(5), one O(6), and one O(8) atom. There are twelve inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Ni(2), one Ni(4), and one Cu(2) atom to form a mixture of distorted corner and edge-sharing OMgCuNi2 trigonal pyramids. In the second O site, O(2) is bonded to one Mg(1), one Ni(2), one Ni(4), and one Cu(2) atom to form corner-sharing OMgCuNi2 tetrahedra. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Mg(1), one Ni(1), one Ni(3), and one Cu(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Mg(1), one Ni(2), one Ni(3), and one Cu(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Ni(3), one Ni(4), and one Cu(3) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Ni(1), one Ni(2), and one Cu(3) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Mg(1), one Ni(1), one Ni(4), and one Cu(1) atom. In the eighth O site, O(8) is bonded to one Mg(1), one Ni(3), one Ni(4), and one Cu(3) atom to form a mixture of distorted corner and edge-sharing OMgCuNi2 tetrahedra. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Ni(1), one Ni(3), and one Cu(2) atom. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Mg(1), one Ni(2), one Ni(3), and one Cu(1) atom. In the eleventh O site, O(11) is bonded to one Mg(1), one Ni(1), one Ni(2), and one Cu(3) atom to form a mixture of distorted corner and edge-sharing OMgCuNi2 tetrahedra. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Mg(1), one Ni(1), one Ni(4), and one Cu(1) atom.
MgCu3(NiO3)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 9-coordinate geometry to one O(1), one O(10), one O(11), one O(12), one O(2), one O(3), one O(4), one O(7), and one O(8) atom. The Mg(1)-O(1) bond length is 2.35 Å. The Mg(1)-O(10) bond length is 2.53 Å. The Mg(1)-O(11) bond length is 2.23 Å. The Mg(1)-O(12) bond length is 2.48 Å. The Mg(1)-O(2) bond length is 2.39 Å. The Mg(1)-O(3) bond length is 2.53 Å. The Mg(1)-O(4) bond length is 2.57 Å. The Mg(1)-O(7) bond length is 2.63 Å. The Mg(1)-O(8) bond length is 2.24 Å. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(11), one O(12), one O(3), one O(6), one O(7), and one O(9) atom to form corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 42-47°. The Ni(1)-O(11) bond length is 1.96 Å. The Ni(1)-O(12) bond length is 2.00 Å. The Ni(1)-O(3) bond length is 1.97 Å. The Ni(1)-O(6) bond length is 1.94 Å. The Ni(1)-O(7) bond length is 1.97 Å. The Ni(1)-O(9) bond length is 1.94 Å. In the second Ni site, Ni(2) is bonded to one O(1), one O(10), one O(11), one O(2), one O(4), and one O(6) atom to form corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 42-48°. The Ni(2)-O(1) bond length is 1.98 Å. The Ni(2)-O(10) bond length is 1.92 Å. The Ni(2)-O(11) bond length is 1.97 Å. The Ni(2)-O(2) bond length is 1.96 Å. The Ni(2)-O(4) bond length is 1.92 Å. The Ni(2)-O(6) bond length is 1.95 Å. In the third Ni site, Ni(3) is bonded to one O(10), one O(3), one O(4), one O(5), one O(8), and one O(9) atom to form corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 42-47°. The Ni(3)-O(10) bond length is 1.99 Å. The Ni(3)-O(3) bond length is 1.97 Å. The Ni(3)-O(4) bond length is 1.97 Å. The Ni(3)-O(5) bond length is 1.94 Å. The Ni(3)-O(8) bond length is 1.96 Å. The Ni(3)-O(9) bond length is 1.94 Å. In the fourth Ni site, Ni(4) is bonded to one O(1), one O(12), one O(2), one O(5), one O(7), and one O(8) atom to form corner-sharing NiO6 octahedra. The corner-sharing octahedral tilt angles range from 43-48°. The Ni(4)-O(1) bond length is 1.98 Å. The Ni(4)-O(12) bond length is 1.92 Å. The Ni(4)-O(2) bond length is 1.96 Å. The Ni(4)-O(5) bond length is 1.95 Å. The Ni(4)-O(7) bond length is 1.91 Å. The Ni(4)-O(8) bond length is 1.97 Å. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a distorted square co-planar geometry to one O(10), one O(12), one O(4), and one O(7) atom. The Cu(1)-O(10) bond length is 1.86 Å. The Cu(1)-O(12) bond length is 1.86 Å. The Cu(1)-O(4) bond length is 1.86 Å. The Cu(1)-O(7) bond length is 1.86 Å. In the second Cu site, Cu(2) is bonded in a square co-planar geometry to one O(1), one O(2), one O(3), and one O(9) atom. The Cu(2)-O(1) bond length is 1.89 Å. The Cu(2)-O(2) bond length is 1.88 Å. The Cu(2)-O(3) bond length is 1.84 Å. The Cu(2)-O(9) bond length is 1.84 Å. In the third Cu site, Cu(3) is bonded in a square co-planar geometry to one O(11), one O(5), one O(6), and one O(8) atom. The Cu(3)-O(11) bond length is 1.85 Å. The Cu(3)-O(5) bond length is 1.85 Å. The Cu(3)-O(6) bond length is 1.85 Å. The Cu(3)-O(8) bond length is 1.85 Å. There are twelve inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Ni(2), one Ni(4), and one Cu(2) atom to form a mixture of distorted corner and edge-sharing OMgCuNi2 trigonal pyramids. In the second O site, O(2) is bonded to one Mg(1), one Ni(2), one Ni(4), and one Cu(2) atom to form corner-sharing OMgCuNi2 tetrahedra. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Mg(1), one Ni(1), one Ni(3), and one Cu(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Mg(1), one Ni(2), one Ni(3), and one Cu(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Ni(3), one Ni(4), and one Cu(3) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Ni(1), one Ni(2), and one Cu(3) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Mg(1), one Ni(1), one Ni(4), and one Cu(1) atom. In the eighth O site, O(8) is bonded to one Mg(1), one Ni(3), one Ni(4), and one Cu(3) atom to form a mixture of distorted corner and edge-sharing OMgCuNi2 tetrahedra. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Ni(1), one Ni(3), and one Cu(2) atom. In the tenth O site, O(10) is bonded in a 4-coordinate geometry to one Mg(1), one Ni(2), one Ni(3), and one Cu(1) atom. In the eleventh O site, O(11) is bonded to one Mg(1), one Ni(1), one Ni(2), and one Cu(3) atom to form a mixture of distorted corner and edge-sharing OMgCuNi2 tetrahedra. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Mg(1), one Ni(1), one Ni(4), and one Cu(1) atom.