MgYb2Cu(GeO3)4 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent O(4), two equivalent O(5), and two equivalent O(6) atoms to form MgO6 octahedra that share edges with two equivalent Ge(1)O4 tetrahedra and edges with two equivalent Ge(2)O4 tetrahedra. Yb(1) is bonded in a 7-coordinate geometry to one O(3), one O(5), one O(6), two equivalent O(1), and two equivalent O(2) atoms. Cu(1) is bonded in a square co-planar geometry to two equivalent O(5) and two equivalent O(6) atoms. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one O(1), one O(3), one O(4), and one O(6) atom to form GeO4 tetrahedra that share corners with two equivalent Ge(2)O4 tetrahedra and  an edgeedge with one Mg(1)O6 octahedra. In the second Ge site, Ge(2) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form GeO4 tetrahedra that share corners with two equivalent Ge(1)O4 tetrahedra and  an edgeedge with one Mg(1)O6 octahedra. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Yb(1) and one Ge(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Yb(1) and one Ge(2) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Yb(1), one Ge(1), and one Ge(2) atom. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one Mg(1), one Ge(1), and one Ge(2) atom. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Yb(1), one Cu(1), and one Ge(2) atom. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Yb(1), one Cu(1), and one Ge(1) atom.
MgYb2Cu(GeO3)4 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent O(4), two equivalent O(5), and two equivalent O(6) atoms to form MgO6 octahedra that share edges with two equivalent Ge(1)O4 tetrahedra and edges with two equivalent Ge(2)O4 tetrahedra. Both Mg(1)-O(4) bond lengths are 2.13 Å. Both Mg(1)-O(5) bond lengths are 2.10 Å. Both Mg(1)-O(6) bond lengths are 2.06 Å. Yb(1) is bonded in a 7-coordinate geometry to one O(3), one O(5), one O(6), two equivalent O(1), and two equivalent O(2) atoms. The Yb(1)-O(3) bond length is 2.91 Å. The Yb(1)-O(5) bond length is 2.33 Å. The Yb(1)-O(6) bond length is 2.36 Å. There is one shorter (2.29 Å) and one longer (2.54 Å) Yb(1)-O(1) bond length. There is one shorter (2.31 Å) and one longer (2.44 Å) Yb(1)-O(2) bond length. Cu(1) is bonded in a square co-planar geometry to two equivalent O(5) and two equivalent O(6) atoms. Both Cu(1)-O(5) bond lengths are 2.01 Å. Both Cu(1)-O(6) bond lengths are 2.00 Å. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one O(1), one O(3), one O(4), and one O(6) atom to form GeO4 tetrahedra that share corners with two equivalent Ge(2)O4 tetrahedra and  an edgeedge with one Mg(1)O6 octahedra. The Ge(1)-O(1) bond length is 1.71 Å. The Ge(1)-O(3) bond length is 1.76 Å. The Ge(1)-O(4) bond length is 1.87 Å. The Ge(1)-O(6) bond length is 1.81 Å. In the second Ge site, Ge(2) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form GeO4 tetrahedra that share corners with two equivalent Ge(1)O4 tetrahedra and  an edgeedge with one Mg(1)O6 octahedra. The Ge(2)-O(2) bond length is 1.71 Å. The Ge(2)-O(3) bond length is 1.77 Å. The Ge(2)-O(4) bond length is 1.84 Å. The Ge(2)-O(5) bond length is 1.81 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Yb(1) and one Ge(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Yb(1) and one Ge(2) atom. In the third O site, O(3) is bonded in a distorted bent 150 degrees geometry to one Yb(1), one Ge(1), and one Ge(2) atom. In the fourth O site, O(4) is bonded in a distorted T-shaped geometry to one Mg(1), one Ge(1), and one Ge(2) atom. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Yb(1), one Cu(1), and one Ge(2) atom. In the sixth O site, O(6) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Yb(1), one Cu(1), and one Ge(1) atom.