Cu2Fe2Ge4O13 crystallizes in the monoclinic P2_1/m space group. Fe(1) is bonded to one O(2), one O(3), one O(6), one O(9), and two equivalent O(4) atoms to form distorted FeO6 octahedra that share  a cornercorner with one Ge(3)O4 tetrahedra, corners with two equivalent Ge(4)O4 tetrahedra, corners with three equivalent Ge(1)O4 tetrahedra, and edges with two equivalent Fe(1)O6 octahedra. Cu(1) is bonded in a square co-planar geometry to one O(3), one O(9), and two equivalent O(1) atoms. There are four inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one O(2), one O(7), and two equivalent O(4) atoms to form distorted GeO4 tetrahedra that share corners with six equivalent Fe(1)O6 octahedra and  a cornercorner with one Ge(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 50-64°. In the second Ge site, Ge(2) is bonded to one O(5), one O(8), and two equivalent O(1) atoms to form corner-sharing GeO4 tetrahedra. In the third Ge site, Ge(3) is bonded to one O(5), one O(7), and two equivalent O(3) atoms to form GeO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra,  a cornercorner with one Ge(1)O4 tetrahedra, and  a cornercorner with one Ge(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 43°. In the fourth Ge site, Ge(4) is bonded to one O(6), one O(8), and two equivalent O(9) atoms to form GeO4 tetrahedra that share corners with four equivalent Fe(1)O6 octahedra and  a cornercorner with one Ge(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 52-61°. There are nine inequivalent O sites. In the first O site, O(6) is bonded in a 3-coordinate geometry to two equivalent Fe(1) and one Ge(4) atom. In the second O site, O(7) is bonded in a bent 150 degrees geometry to one Ge(1) and one Ge(3) atom. In the third O site, O(8) is bonded in a bent 120 degrees geometry to one Ge(2) and one Ge(4) atom. In the fourth O site, O(9) is bonded in a trigonal planar geometry to one Fe(1), one Cu(1), and one Ge(4) atom. In the fifth O site, O(1) is bonded in a trigonal planar geometry to two equivalent Cu(1) and one Ge(2) atom. In the sixth O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Fe(1) and one Ge(1) atom. In the seventh O site, O(3) is bonded in a distorted trigonal planar geometry to one Fe(1), one Cu(1), and one Ge(3) atom. In the eighth O site, O(4) is bonded in a distorted trigonal planar geometry to two equivalent Fe(1) and one Ge(1) atom. In the ninth O site, O(5) is bonded in a bent 120 degrees geometry to one Ge(2) and one Ge(3) atom.
Cu2Fe2Ge4O13 crystallizes in the monoclinic P2_1/m space group. Fe(1) is bonded to one O(2), one O(3), one O(6), one O(9), and two equivalent O(4) atoms to form distorted FeO6 octahedra that share  a cornercorner with one Ge(3)O4 tetrahedra, corners with two equivalent Ge(4)O4 tetrahedra, corners with three equivalent Ge(1)O4 tetrahedra, and edges with two equivalent Fe(1)O6 octahedra. The Fe(1)-O(2) bond length is 2.09 Å. The Fe(1)-O(3) bond length is 2.03 Å. The Fe(1)-O(6) bond length is 2.10 Å. The Fe(1)-O(9) bond length is 2.05 Å. There is one shorter (2.00 Å) and one longer (2.10 Å) Fe(1)-O(4) bond length. Cu(1) is bonded in a square co-planar geometry to one O(3), one O(9), and two equivalent O(1) atoms. The Cu(1)-O(3) bond length is 2.03 Å. The Cu(1)-O(9) bond length is 1.95 Å. There is one shorter (1.95 Å) and one longer (1.97 Å) Cu(1)-O(1) bond length. There are four inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one O(2), one O(7), and two equivalent O(4) atoms to form distorted GeO4 tetrahedra that share corners with six equivalent Fe(1)O6 octahedra and  a cornercorner with one Ge(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 50-64°. The Ge(1)-O(2) bond length is 1.78 Å. The Ge(1)-O(7) bond length is 1.76 Å. Both Ge(1)-O(4) bond lengths are 1.78 Å. In the second Ge site, Ge(2) is bonded to one O(5), one O(8), and two equivalent O(1) atoms to form corner-sharing GeO4 tetrahedra. The Ge(2)-O(5) bond length is 1.77 Å. The Ge(2)-O(8) bond length is 1.77 Å. Both Ge(2)-O(1) bond lengths are 1.76 Å. In the third Ge site, Ge(3) is bonded to one O(5), one O(7), and two equivalent O(3) atoms to form GeO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra,  a cornercorner with one Ge(1)O4 tetrahedra, and  a cornercorner with one Ge(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 43°. The Ge(3)-O(5) bond length is 1.80 Å. The Ge(3)-O(7) bond length is 1.72 Å. Both Ge(3)-O(3) bond lengths are 1.78 Å. In the fourth Ge site, Ge(4) is bonded to one O(6), one O(8), and two equivalent O(9) atoms to form GeO4 tetrahedra that share corners with four equivalent Fe(1)O6 octahedra and  a cornercorner with one Ge(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 52-61°. The Ge(4)-O(6) bond length is 1.77 Å. The Ge(4)-O(8) bond length is 1.80 Å. Both Ge(4)-O(9) bond lengths are 1.78 Å. There are nine inequivalent O sites. In the first O site, O(6) is bonded in a 3-coordinate geometry to two equivalent Fe(1) and one Ge(4) atom. In the second O site, O(7) is bonded in a bent 150 degrees geometry to one Ge(1) and one Ge(3) atom. In the third O site, O(8) is bonded in a bent 120 degrees geometry to one Ge(2) and one Ge(4) atom. In the fourth O site, O(9) is bonded in a trigonal planar geometry to one Fe(1), one Cu(1), and one Ge(4) atom. In the fifth O site, O(1) is bonded in a trigonal planar geometry to two equivalent Cu(1) and one Ge(2) atom. In the sixth O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Fe(1) and one Ge(1) atom. In the seventh O site, O(3) is bonded in a distorted trigonal planar geometry to one Fe(1), one Cu(1), and one Ge(3) atom. In the eighth O site, O(4) is bonded in a distorted trigonal planar geometry to two equivalent Fe(1) and one Ge(1) atom. In the ninth O site, O(5) is bonded in a bent 120 degrees geometry to one Ge(2) and one Ge(3) atom.