MgZn(FeO2)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(4), and two equivalent O(3) atoms. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(2), one O(7), two equivalent O(4), and two equivalent O(5) atoms to form distorted FeO6 octahedra that share corners with two equivalent Fe(3)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Fe(4)O6 pentagonal pyramids, and edges with two equivalent Zn(1)O5 square pyramids. The corner-sharing octahedral tilt angles are 51°. In the second Fe site, Fe(2) is bonded in a 5-coordinate geometry to one O(8), two equivalent O(3), and two equivalent O(6) atoms. In the third Fe site, Fe(3) is bonded to one O(1), one O(6), two equivalent O(2), and two equivalent O(8) atoms to form FeO6 octahedra that share corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Zn(1)O5 square pyramids, edges with two equivalent Fe(3)O6 octahedra, and edges with two equivalent Fe(4)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 51°. In the fourth Fe site, Fe(4) is bonded to one O(5), one O(8), two equivalent O(1), and two equivalent O(7) atoms to form distorted FeO6 pentagonal pyramids that share corners with two equivalent Zn(1)O5 square pyramids, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, edges with two equivalent Fe(4)O6 pentagonal pyramids, and  an edgeedge with one Zn(1)O5 square pyramid. Zn(1) is bonded to one O(4), two equivalent O(6), and two equivalent O(7) atoms to form ZnO5 square pyramids that share corners with two equivalent Fe(3)O6 octahedra, corners with two equivalent Fe(4)O6 pentagonal pyramids, edges with two equivalent Fe(1)O6 octahedra,  an edgeedge with one Fe(4)O6 pentagonal pyramid, and edges with two equivalent Zn(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 50-51°. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Fe(3), and two equivalent Fe(4) atoms to form OMgFe3 tetrahedra that share corners with two equivalent O(7)Zn2Fe3 square pyramids, corners with two equivalent O(1)MgFe3 tetrahedra,  a cornercorner with one O(6)Zn2Fe3 trigonal bipyramid,  an edgeedge with one O(7)Zn2Fe3 square pyramid, and edges with two equivalent O(8)Fe4 trigonal pyramids. In the second O site, O(2) is bonded in a trigonal planar geometry to one Fe(1) and two equivalent Fe(3) atoms. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Mg(1) and two equivalent Fe(2) atoms. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), two equivalent Fe(1), and one Zn(1) atom. In the fifth O site, O(5) is bonded in a trigonal non-coplanar geometry to one Fe(4) and two equivalent Fe(1) atoms. In the sixth O site, O(6) is bonded to one Fe(3), two equivalent Fe(2), and two equivalent Zn(1) atoms to form distorted OZn2Fe3 trigonal bipyramids that share corners with two equivalent O(7)Zn2Fe3 square pyramids,  a cornercorner with one O(1)MgFe3 tetrahedra,  an edgeedge with one O(7)Zn2Fe3 square pyramid, edges with two equivalent O(6)Zn2Fe3 trigonal bipyramids, and edges with two equivalent O(8)Fe4 trigonal pyramids. In the seventh O site, O(7) is bonded to one Fe(1), two equivalent Fe(4), and two equivalent Zn(1) atoms to form OZn2Fe3 square pyramids that share corners with two equivalent O(1)MgFe3 tetrahedra, corners with two equivalent O(6)Zn2Fe3 trigonal bipyramids, corners with two equivalent O(8)Fe4 trigonal pyramids, edges with two equivalent O(7)Zn2Fe3 square pyramids,  an edgeedge with one O(1)MgFe3 tetrahedra, and  an edgeedge with one O(6)Zn2Fe3 trigonal bipyramid. In the eighth O site, O(8) is bonded to one Fe(2), one Fe(4), and two equivalent Fe(3) atoms to form distorted OFe4 trigonal pyramids that share corners with two equivalent O(7)Zn2Fe3 square pyramids, corners with two equivalent O(8)Fe4 trigonal pyramids, edges with two equivalent O(1)MgFe3 tetrahedra, and edges with two equivalent O(6)Zn2Fe3 trigonal bipyramids.
MgZn(FeO2)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(4), and two equivalent O(3) atoms. The Mg(1)-O(1) bond length is 1.91 Å. The Mg(1)-O(4) bond length is 1.96 Å. There is one shorter (2.04 Å) and one longer (2.05 Å) Mg(1)-O(3) bond length. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(2), one O(7), two equivalent O(4), and two equivalent O(5) atoms to form distorted FeO6 octahedra that share corners with two equivalent Fe(3)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Fe(4)O6 pentagonal pyramids, and edges with two equivalent Zn(1)O5 square pyramids. The corner-sharing octahedral tilt angles are 51°. The Fe(1)-O(2) bond length is 2.00 Å. The Fe(1)-O(7) bond length is 2.35 Å. There is one shorter (2.07 Å) and one longer (2.08 Å) Fe(1)-O(4) bond length. Both Fe(1)-O(5) bond lengths are 1.99 Å. In the second Fe site, Fe(2) is bonded in a 5-coordinate geometry to one O(8), two equivalent O(3), and two equivalent O(6) atoms. The Fe(2)-O(8) bond length is 1.87 Å. There is one shorter (2.03 Å) and one longer (2.04 Å) Fe(2)-O(3) bond length. There is one shorter (2.13 Å) and one longer (2.14 Å) Fe(2)-O(6) bond length. In the third Fe site, Fe(3) is bonded to one O(1), one O(6), two equivalent O(2), and two equivalent O(8) atoms to form FeO6 octahedra that share corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Zn(1)O5 square pyramids, edges with two equivalent Fe(3)O6 octahedra, and edges with two equivalent Fe(4)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 51°. The Fe(3)-O(1) bond length is 2.10 Å. The Fe(3)-O(6) bond length is 2.16 Å. Both Fe(3)-O(2) bond lengths are 1.96 Å. Both Fe(3)-O(8) bond lengths are 2.11 Å. In the fourth Fe site, Fe(4) is bonded to one O(5), one O(8), two equivalent O(1), and two equivalent O(7) atoms to form distorted FeO6 pentagonal pyramids that share corners with two equivalent Zn(1)O5 square pyramids, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, edges with two equivalent Fe(4)O6 pentagonal pyramids, and  an edgeedge with one Zn(1)O5 square pyramid. The Fe(4)-O(5) bond length is 1.93 Å. The Fe(4)-O(8) bond length is 2.14 Å. There is one shorter (2.04 Å) and one longer (2.05 Å) Fe(4)-O(1) bond length. There is one shorter (2.15 Å) and one longer (2.19 Å) Fe(4)-O(7) bond length. Zn(1) is bonded to one O(4), two equivalent O(6), and two equivalent O(7) atoms to form ZnO5 square pyramids that share corners with two equivalent Fe(3)O6 octahedra, corners with two equivalent Fe(4)O6 pentagonal pyramids, edges with two equivalent Fe(1)O6 octahedra,  an edgeedge with one Fe(4)O6 pentagonal pyramid, and edges with two equivalent Zn(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 50-51°. The Zn(1)-O(4) bond length is 2.07 Å. There is one shorter (2.17 Å) and one longer (2.20 Å) Zn(1)-O(6) bond length. Both Zn(1)-O(7) bond lengths are 2.05 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Fe(3), and two equivalent Fe(4) atoms to form OMgFe3 tetrahedra that share corners with two equivalent O(7)Zn2Fe3 square pyramids, corners with two equivalent O(1)MgFe3 tetrahedra,  a cornercorner with one O(6)Zn2Fe3 trigonal bipyramid,  an edgeedge with one O(7)Zn2Fe3 square pyramid, and edges with two equivalent O(8)Fe4 trigonal pyramids. In the second O site, O(2) is bonded in a trigonal planar geometry to one Fe(1) and two equivalent Fe(3) atoms. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to two equivalent Mg(1) and two equivalent Fe(2) atoms. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), two equivalent Fe(1), and one Zn(1) atom. In the fifth O site, O(5) is bonded in a trigonal non-coplanar geometry to one Fe(4) and two equivalent Fe(1) atoms. In the sixth O site, O(6) is bonded to one Fe(3), two equivalent Fe(2), and two equivalent Zn(1) atoms to form distorted OZn2Fe3 trigonal bipyramids that share corners with two equivalent O(7)Zn2Fe3 square pyramids,  a cornercorner with one O(1)MgFe3 tetrahedra,  an edgeedge with one O(7)Zn2Fe3 square pyramid, edges with two equivalent O(6)Zn2Fe3 trigonal bipyramids, and edges with two equivalent O(8)Fe4 trigonal pyramids. In the seventh O site, O(7) is bonded to one Fe(1), two equivalent Fe(4), and two equivalent Zn(1) atoms to form OZn2Fe3 square pyramids that share corners with two equivalent O(1)MgFe3 tetrahedra, corners with two equivalent O(6)Zn2Fe3 trigonal bipyramids, corners with two equivalent O(8)Fe4 trigonal pyramids, edges with two equivalent O(7)Zn2Fe3 square pyramids,  an edgeedge with one O(1)MgFe3 tetrahedra, and  an edgeedge with one O(6)Zn2Fe3 trigonal bipyramid. In the eighth O site, O(8) is bonded to one Fe(2), one Fe(4), and two equivalent Fe(3) atoms to form distorted OFe4 trigonal pyramids that share corners with two equivalent O(7)Zn2Fe3 square pyramids, corners with two equivalent O(8)Fe4 trigonal pyramids, edges with two equivalent O(1)MgFe3 tetrahedra, and edges with two equivalent O(6)Zn2Fe3 trigonal bipyramids.