MgZn2(NiO2)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(8), two equivalent O(1), and two equivalent O(5) atoms to form MgO5 square pyramids that share corners with two equivalent Ni(3)O6 octahedra,  a cornercorner with one Zn(1)O6 pentagonal pyramid, edges with two equivalent Ni(4)O6 octahedra, edges with three equivalent Ni(3)O6 octahedra, and edges with two equivalent Mg(1)O5 square pyramids. The corner-sharing octahedral tilt angles are 2°. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(3), two equivalent O(4), and two equivalent O(7) atoms to form NiO5 trigonal bipyramids that share corners with two equivalent Ni(2)O6 octahedra,  a cornercorner with one Zn(1)O6 pentagonal pyramid, edges with three equivalent Ni(2)O6 octahedra, and edges with two equivalent Ni(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 25-26°. In the second Ni site, Ni(2) is bonded to one O(4), one O(6), two equivalent O(3), and two equivalent O(7) atoms to form NiO6 octahedra that share  a cornercorner with one Ni(4)O6 octahedra, corners with four equivalent Zn(1)O6 pentagonal pyramids, corners with two equivalent Ni(1)O5 trigonal bipyramids, edges with two equivalent Ni(2)O6 octahedra, and edges with three equivalent Ni(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 63°. In the third Ni site, Ni(3) is bonded to one O(2), one O(5), two equivalent O(1), and two equivalent O(8) atoms to form NiO6 octahedra that share corners with two equivalent Ni(4)O6 octahedra, corners with two equivalent Mg(1)O5 square pyramids, edges with two equivalent Ni(3)O6 octahedra, edges with three equivalent Ni(4)O6 octahedra, edges with two equivalent Zn(1)O6 pentagonal pyramids, and edges with three equivalent Mg(1)O5 square pyramids. The corner-sharing octahedral tilt angles are 1°. In the fourth Ni site, Ni(4) is bonded to one O(1), one O(6), two equivalent O(2), and two equivalent O(8) atoms to form NiO6 octahedra that share  a cornercorner with one Ni(2)O6 octahedra, corners with two equivalent Ni(3)O6 octahedra, corners with two equivalent Zn(1)O6 pentagonal pyramids, edges with two equivalent Ni(4)O6 octahedra, edges with three equivalent Ni(3)O6 octahedra, edges with three equivalent Zn(1)O6 pentagonal pyramids, and edges with two equivalent Mg(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 1-63°. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded to one O(3), one O(8), two equivalent O(2), and two equivalent O(6) atoms to form distorted ZnO6 pentagonal pyramids that share corners with two equivalent Ni(4)O6 octahedra, corners with four equivalent Ni(2)O6 octahedra,  a cornercorner with one Mg(1)O5 square pyramid,  a cornercorner with one Ni(1)O5 trigonal bipyramid, edges with two equivalent Ni(3)O6 octahedra, edges with three equivalent Ni(4)O6 octahedra, and edges with two equivalent Zn(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 21-74°. In the second Zn site, Zn(2) is bonded in a 5-coordinate geometry to one O(7), two equivalent O(4), and two equivalent O(5) atoms. There are eight inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(1), one Ni(4), and two equivalent Ni(3) atoms to form OMg2Ni3 square pyramids that share corners with two equivalent O(8)MgZnNi4 octahedra,  a cornercorner with one O(6)Zn2Ni2 tetrahedra, corners with four equivalent O(5)Mg2Zn2Ni trigonal bipyramids, edges with three equivalent O(8)MgZnNi4 octahedra, edges with two equivalent O(1)Mg2Ni3 square pyramids, edges with two equivalent O(2)Zn2Ni3 square pyramids, and  an edgeedge with one O(5)Mg2Zn2Ni trigonal bipyramid. The corner-sharing octahedral tilt angles range from 5-6°. In the second O site, O(2) is bonded to one Ni(3), two equivalent Ni(4), and two equivalent Zn(1) atoms to form distorted OZn2Ni3 square pyramids that share corners with two equivalent O(8)MgZnNi4 octahedra, corners with four equivalent O(6)Zn2Ni2 tetrahedra,  a cornercorner with one O(5)Mg2Zn2Ni trigonal bipyramid, edges with three equivalent O(8)MgZnNi4 octahedra, edges with two equivalent O(1)Mg2Ni3 square pyramids, edges with two equivalent O(2)Zn2Ni3 square pyramids, and  an edgeedge with one O(6)Zn2Ni2 tetrahedra. The corner-sharing octahedral tilt angles are 12°. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Ni(1), two equivalent Ni(2), and one Zn(1) atom. In the fourth O site, O(4) is bonded to one Ni(2), two equivalent Ni(1), and two equivalent Zn(2) atoms to form OZn2Ni3 square pyramids that share  a cornercorner with one O(6)Zn2Ni2 tetrahedra, corners with two equivalent O(5)Mg2Zn2Ni trigonal bipyramids, corners with two equivalent O(7)ZnNi4 trigonal bipyramids, edges with two equivalent O(4)Zn2Ni3 square pyramids,  an edgeedge with one O(5)Mg2Zn2Ni trigonal bipyramid, and edges with three equivalent O(7)ZnNi4 trigonal bipyramids. In the fifth O site, O(5) is bonded to two equivalent Mg(1), one Ni(3), and two equivalent Zn(2) atoms to form distorted OMg2Zn2Ni trigonal bipyramids that share  a cornercorner with one O(2)Zn2Ni3 square pyramid, corners with two equivalent O(4)Zn2Ni3 square pyramids, corners with four equivalent O(1)Mg2Ni3 square pyramids, corners with two equivalent O(7)ZnNi4 trigonal bipyramids, edges with two equivalent O(8)MgZnNi4 octahedra,  an edgeedge with one O(1)Mg2Ni3 square pyramid,  an edgeedge with one O(4)Zn2Ni3 square pyramid, and edges with two equivalent O(5)Mg2Zn2Ni trigonal bipyramids. In the sixth O site, O(6) is bonded to one Ni(2), one Ni(4), and two equivalent Zn(1) atoms to form OZn2Ni2 tetrahedra that share  a cornercorner with one O(1)Mg2Ni3 square pyramid,  a cornercorner with one O(4)Zn2Ni3 square pyramid, corners with four equivalent O(2)Zn2Ni3 square pyramids, corners with two equivalent O(6)Zn2Ni2 tetrahedra, corners with two equivalent O(7)ZnNi4 trigonal bipyramids, edges with two equivalent O(8)MgZnNi4 octahedra, and  an edgeedge with one O(2)Zn2Ni3 square pyramid. In the seventh O site, O(7) is bonded to two equivalent Ni(1), two equivalent Ni(2), and one Zn(2) atom to form distorted OZnNi4 trigonal bipyramids that share corners with two equivalent O(4)Zn2Ni3 square pyramids, corners with two equivalent O(6)Zn2Ni2 tetrahedra, corners with two equivalent O(5)Mg2Zn2Ni trigonal bipyramids, edges with three equivalent O(4)Zn2Ni3 square pyramids, and edges with two equivalent O(7)ZnNi4 trigonal bipyramids. In the eighth O site, O(8) is bonded to one Mg(1), two equivalent Ni(3), two equivalent Ni(4), and one Zn(1) atom to form OMgZnNi4 octahedra that share corners with two equivalent O(1)Mg2Ni3 square pyramids, corners with two equivalent O(2)Zn2Ni3 square pyramids, edges with two equivalent O(8)MgZnNi4 octahedra, edges with three equivalent O(1)Mg2Ni3 square pyramids, edges with three equivalent O(2)Zn2Ni3 square pyramids, edges with two equivalent O(6)Zn2Ni2 tetrahedra, and edges with two equivalent O(5)Mg2Zn2Ni trigonal bipyramids.
MgZn2(NiO2)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(8), two equivalent O(1), and two equivalent O(5) atoms to form MgO5 square pyramids that share corners with two equivalent Ni(3)O6 octahedra,  a cornercorner with one Zn(1)O6 pentagonal pyramid, edges with two equivalent Ni(4)O6 octahedra, edges with three equivalent Ni(3)O6 octahedra, and edges with two equivalent Mg(1)O5 square pyramids. The corner-sharing octahedral tilt angles are 2°. The Mg(1)-O(8) bond length is 2.00 Å. There is one shorter (2.00 Å) and one longer (2.02 Å) Mg(1)-O(1) bond length. There is one shorter (2.10 Å) and one longer (2.11 Å) Mg(1)-O(5) bond length. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(3), two equivalent O(4), and two equivalent O(7) atoms to form NiO5 trigonal bipyramids that share corners with two equivalent Ni(2)O6 octahedra,  a cornercorner with one Zn(1)O6 pentagonal pyramid, edges with three equivalent Ni(2)O6 octahedra, and edges with two equivalent Ni(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 25-26°. The Ni(1)-O(3) bond length is 1.99 Å. There is one shorter (2.00 Å) and one longer (2.06 Å) Ni(1)-O(4) bond length. There is one shorter (1.99 Å) and one longer (2.06 Å) Ni(1)-O(7) bond length. In the second Ni site, Ni(2) is bonded to one O(4), one O(6), two equivalent O(3), and two equivalent O(7) atoms to form NiO6 octahedra that share  a cornercorner with one Ni(4)O6 octahedra, corners with four equivalent Zn(1)O6 pentagonal pyramids, corners with two equivalent Ni(1)O5 trigonal bipyramids, edges with two equivalent Ni(2)O6 octahedra, and edges with three equivalent Ni(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 63°. The Ni(2)-O(4) bond length is 2.02 Å. The Ni(2)-O(6) bond length is 1.98 Å. There is one shorter (1.92 Å) and one longer (2.10 Å) Ni(2)-O(3) bond length. There is one shorter (2.14 Å) and one longer (2.21 Å) Ni(2)-O(7) bond length. In the third Ni site, Ni(3) is bonded to one O(2), one O(5), two equivalent O(1), and two equivalent O(8) atoms to form NiO6 octahedra that share corners with two equivalent Ni(4)O6 octahedra, corners with two equivalent Mg(1)O5 square pyramids, edges with two equivalent Ni(3)O6 octahedra, edges with three equivalent Ni(4)O6 octahedra, edges with two equivalent Zn(1)O6 pentagonal pyramids, and edges with three equivalent Mg(1)O5 square pyramids. The corner-sharing octahedral tilt angles are 1°. The Ni(3)-O(2) bond length is 2.00 Å. The Ni(3)-O(5) bond length is 2.13 Å. There is one shorter (2.05 Å) and one longer (2.06 Å) Ni(3)-O(1) bond length. Both Ni(3)-O(8) bond lengths are 2.11 Å. In the fourth Ni site, Ni(4) is bonded to one O(1), one O(6), two equivalent O(2), and two equivalent O(8) atoms to form NiO6 octahedra that share  a cornercorner with one Ni(2)O6 octahedra, corners with two equivalent Ni(3)O6 octahedra, corners with two equivalent Zn(1)O6 pentagonal pyramids, edges with two equivalent Ni(4)O6 octahedra, edges with three equivalent Ni(3)O6 octahedra, edges with three equivalent Zn(1)O6 pentagonal pyramids, and edges with two equivalent Mg(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 1-63°. The Ni(4)-O(1) bond length is 2.18 Å. The Ni(4)-O(6) bond length is 2.02 Å. There is one shorter (2.03 Å) and one longer (2.11 Å) Ni(4)-O(2) bond length. There is one shorter (2.10 Å) and one longer (2.13 Å) Ni(4)-O(8) bond length. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded to one O(3), one O(8), two equivalent O(2), and two equivalent O(6) atoms to form distorted ZnO6 pentagonal pyramids that share corners with two equivalent Ni(4)O6 octahedra, corners with four equivalent Ni(2)O6 octahedra,  a cornercorner with one Mg(1)O5 square pyramid,  a cornercorner with one Ni(1)O5 trigonal bipyramid, edges with two equivalent Ni(3)O6 octahedra, edges with three equivalent Ni(4)O6 octahedra, and edges with two equivalent Zn(1)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles range from 21-74°. The Zn(1)-O(3) bond length is 2.12 Å. The Zn(1)-O(8) bond length is 2.41 Å. There is one shorter (2.09 Å) and one longer (2.22 Å) Zn(1)-O(2) bond length. There is one shorter (2.00 Å) and one longer (2.07 Å) Zn(1)-O(6) bond length. In the second Zn site, Zn(2) is bonded in a 5-coordinate geometry to one O(7), two equivalent O(4), and two equivalent O(5) atoms. The Zn(2)-O(7) bond length is 2.01 Å. There is one shorter (2.14 Å) and one longer (2.17 Å) Zn(2)-O(4) bond length. There is one shorter (2.06 Å) and one longer (2.09 Å) Zn(2)-O(5) bond length. There are eight inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(1), one Ni(4), and two equivalent Ni(3) atoms to form OMg2Ni3 square pyramids that share corners with two equivalent O(8)MgZnNi4 octahedra,  a cornercorner with one O(6)Zn2Ni2 tetrahedra, corners with four equivalent O(5)Mg2Zn2Ni trigonal bipyramids, edges with three equivalent O(8)MgZnNi4 octahedra, edges with two equivalent O(1)Mg2Ni3 square pyramids, edges with two equivalent O(2)Zn2Ni3 square pyramids, and  an edgeedge with one O(5)Mg2Zn2Ni trigonal bipyramid. The corner-sharing octahedral tilt angles range from 5-6°. In the second O site, O(2) is bonded to one Ni(3), two equivalent Ni(4), and two equivalent Zn(1) atoms to form distorted OZn2Ni3 square pyramids that share corners with two equivalent O(8)MgZnNi4 octahedra, corners with four equivalent O(6)Zn2Ni2 tetrahedra,  a cornercorner with one O(5)Mg2Zn2Ni trigonal bipyramid, edges with three equivalent O(8)MgZnNi4 octahedra, edges with two equivalent O(1)Mg2Ni3 square pyramids, edges with two equivalent O(2)Zn2Ni3 square pyramids, and  an edgeedge with one O(6)Zn2Ni2 tetrahedra. The corner-sharing octahedral tilt angles are 12°. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Ni(1), two equivalent Ni(2), and one Zn(1) atom. In the fourth O site, O(4) is bonded to one Ni(2), two equivalent Ni(1), and two equivalent Zn(2) atoms to form OZn2Ni3 square pyramids that share  a cornercorner with one O(6)Zn2Ni2 tetrahedra, corners with two equivalent O(5)Mg2Zn2Ni trigonal bipyramids, corners with two equivalent O(7)ZnNi4 trigonal bipyramids, edges with two equivalent O(4)Zn2Ni3 square pyramids,  an edgeedge with one O(5)Mg2Zn2Ni trigonal bipyramid, and edges with three equivalent O(7)ZnNi4 trigonal bipyramids. In the fifth O site, O(5) is bonded to two equivalent Mg(1), one Ni(3), and two equivalent Zn(2) atoms to form distorted OMg2Zn2Ni trigonal bipyramids that share  a cornercorner with one O(2)Zn2Ni3 square pyramid, corners with two equivalent O(4)Zn2Ni3 square pyramids, corners with four equivalent O(1)Mg2Ni3 square pyramids, corners with two equivalent O(7)ZnNi4 trigonal bipyramids, edges with two equivalent O(8)MgZnNi4 octahedra,  an edgeedge with one O(1)Mg2Ni3 square pyramid,  an edgeedge with one O(4)Zn2Ni3 square pyramid, and edges with two equivalent O(5)Mg2Zn2Ni trigonal bipyramids. In the sixth O site, O(6) is bonded to one Ni(2), one Ni(4), and two equivalent Zn(1) atoms to form OZn2Ni2 tetrahedra that share  a cornercorner with one O(1)Mg2Ni3 square pyramid,  a cornercorner with one O(4)Zn2Ni3 square pyramid, corners with four equivalent O(2)Zn2Ni3 square pyramids, corners with two equivalent O(6)Zn2Ni2 tetrahedra, corners with two equivalent O(7)ZnNi4 trigonal bipyramids, edges with two equivalent O(8)MgZnNi4 octahedra, and  an edgeedge with one O(2)Zn2Ni3 square pyramid. In the seventh O site, O(7) is bonded to two equivalent Ni(1), two equivalent Ni(2), and one Zn(2) atom to form distorted OZnNi4 trigonal bipyramids that share corners with two equivalent O(4)Zn2Ni3 square pyramids, corners with two equivalent O(6)Zn2Ni2 tetrahedra, corners with two equivalent O(5)Mg2Zn2Ni trigonal bipyramids, edges with three equivalent O(4)Zn2Ni3 square pyramids, and edges with two equivalent O(7)ZnNi4 trigonal bipyramids. In the eighth O site, O(8) is bonded to one Mg(1), two equivalent Ni(3), two equivalent Ni(4), and one Zn(1) atom to form OMgZnNi4 octahedra that share corners with two equivalent O(1)Mg2Ni3 square pyramids, corners with two equivalent O(2)Zn2Ni3 square pyramids, edges with two equivalent O(8)MgZnNi4 octahedra, edges with three equivalent O(1)Mg2Ni3 square pyramids, edges with three equivalent O(2)Zn2Ni3 square pyramids, edges with two equivalent O(6)Zn2Ni2 tetrahedra, and edges with two equivalent O(5)Mg2Zn2Ni trigonal bipyramids.