Fe2Zn(CuO4)2 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(2), one O(4), and one O(7) atom to form FeO4 tetrahedra that share corners with three equivalent Zn(1)O6 octahedra and corners with two equivalent Cu(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 38-50°. In the second Fe site, Fe(2) is bonded to one O(3), one O(5), one O(6), and one O(8) atom to form FeO4 tetrahedra that share corners with three equivalent Zn(1)O6 octahedra and corners with three equivalent Cu(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 59-61°. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(1), one O(3), one O(5), one O(6), and one O(7) atom to form CuO5 trigonal bipyramids that share corners with two equivalent Fe(1)O4 tetrahedra, corners with three equivalent Fe(2)O4 tetrahedra, and edges with two equivalent Zn(1)O6 octahedra. In the second Cu site, Cu(2) is bonded in a rectangular see-saw-like geometry to one O(2), one O(4), one O(6), and one O(8) atom. Zn(1) is bonded to one O(1), one O(4), one O(7), one O(8), and two equivalent O(3) atoms to form ZnO6 octahedra that share corners with three equivalent Fe(1)O4 tetrahedra, corners with three equivalent Fe(2)O4 tetrahedra,  an edgeedge with one Zn(1)O6 octahedra, and edges with two equivalent Cu(1)O5 trigonal bipyramids. There are eight inequivalent O sites. In the first O site, O(7) is bonded in a distorted trigonal planar geometry to one Fe(1), one Cu(1), and one Zn(1) atom. In the second O site, O(8) is bonded in a trigonal planar geometry to one Fe(2), one Cu(2), and one Zn(1) atom. In the third O site, O(1) is bonded in a trigonal planar geometry to one Fe(1), one Cu(1), and one Zn(1) atom. In the fourth O site, O(2) is bonded in a bent 150 degrees geometry to one Fe(1) and one Cu(2) atom. In the fifth O site, O(3) is bonded to one Fe(2), one Cu(1), and two equivalent Zn(1) atoms to form distorted edge-sharing OZn2FeCu tetrahedra. In the sixth O site, O(4) is bonded in a distorted trigonal planar geometry to one Fe(1), one Cu(2), and one Zn(1) atom. In the seventh O site, O(5) is bonded in a bent 120 degrees geometry to one Fe(2) and one Cu(1) atom. In the eighth O site, O(6) is bonded in a distorted trigonal planar geometry to one Fe(2), one Cu(1), and one Cu(2) atom.
Fe2Zn(CuO4)2 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(2), one O(4), and one O(7) atom to form FeO4 tetrahedra that share corners with three equivalent Zn(1)O6 octahedra and corners with two equivalent Cu(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 38-50°. The Fe(1)-O(1) bond length is 1.84 Å. The Fe(1)-O(2) bond length is 1.81 Å. The Fe(1)-O(4) bond length is 1.85 Å. The Fe(1)-O(7) bond length is 1.77 Å. In the second Fe site, Fe(2) is bonded to one O(3), one O(5), one O(6), and one O(8) atom to form FeO4 tetrahedra that share corners with three equivalent Zn(1)O6 octahedra and corners with three equivalent Cu(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 59-61°. The Fe(2)-O(3) bond length is 1.92 Å. The Fe(2)-O(5) bond length is 1.84 Å. The Fe(2)-O(6) bond length is 1.92 Å. The Fe(2)-O(8) bond length is 1.86 Å. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(1), one O(3), one O(5), one O(6), and one O(7) atom to form CuO5 trigonal bipyramids that share corners with two equivalent Fe(1)O4 tetrahedra, corners with three equivalent Fe(2)O4 tetrahedra, and edges with two equivalent Zn(1)O6 octahedra. The Cu(1)-O(1) bond length is 1.84 Å. The Cu(1)-O(3) bond length is 1.94 Å. The Cu(1)-O(5) bond length is 1.80 Å. The Cu(1)-O(6) bond length is 1.89 Å. The Cu(1)-O(7) bond length is 2.12 Å. In the second Cu site, Cu(2) is bonded in a rectangular see-saw-like geometry to one O(2), one O(4), one O(6), and one O(8) atom. The Cu(2)-O(2) bond length is 1.83 Å. The Cu(2)-O(4) bond length is 1.84 Å. The Cu(2)-O(6) bond length is 1.88 Å. The Cu(2)-O(8) bond length is 1.83 Å. Zn(1) is bonded to one O(1), one O(4), one O(7), one O(8), and two equivalent O(3) atoms to form ZnO6 octahedra that share corners with three equivalent Fe(1)O4 tetrahedra, corners with three equivalent Fe(2)O4 tetrahedra,  an edgeedge with one Zn(1)O6 octahedra, and edges with two equivalent Cu(1)O5 trigonal bipyramids. The Zn(1)-O(1) bond length is 2.06 Å. The Zn(1)-O(4) bond length is 2.12 Å. The Zn(1)-O(7) bond length is 2.04 Å. The Zn(1)-O(8) bond length is 2.00 Å. There is one shorter (2.06 Å) and one longer (2.19 Å) Zn(1)-O(3) bond length. There are eight inequivalent O sites. In the first O site, O(7) is bonded in a distorted trigonal planar geometry to one Fe(1), one Cu(1), and one Zn(1) atom. In the second O site, O(8) is bonded in a trigonal planar geometry to one Fe(2), one Cu(2), and one Zn(1) atom. In the third O site, O(1) is bonded in a trigonal planar geometry to one Fe(1), one Cu(1), and one Zn(1) atom. In the fourth O site, O(2) is bonded in a bent 150 degrees geometry to one Fe(1) and one Cu(2) atom. In the fifth O site, O(3) is bonded to one Fe(2), one Cu(1), and two equivalent Zn(1) atoms to form distorted edge-sharing OZn2FeCu tetrahedra. In the sixth O site, O(4) is bonded in a distorted trigonal planar geometry to one Fe(1), one Cu(2), and one Zn(1) atom. In the seventh O site, O(5) is bonded in a bent 120 degrees geometry to one Fe(2) and one Cu(1) atom. In the eighth O site, O(6) is bonded in a distorted trigonal planar geometry to one Fe(2), one Cu(1), and one Cu(2) atom.