Lu3(CuGe)4 crystallizes in the orthorhombic Immm space group. There are two inequivalent Lu sites. In the first Lu site, Lu(1) is bonded to two equivalent Ge(1) and four equivalent Ge(2) atoms to form distorted edge-sharing LuGe6 octahedra. In the second Lu site, Lu(2) is bonded in a 12-coordinate geometry to six equivalent Cu(1), two equivalent Ge(1), and four equivalent Ge(2) atoms. Cu(1) is bonded in a 8-coordinate geometry to three equivalent Lu(2), one Cu(1), one Ge(2), and three equivalent Ge(1) atoms. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded in a 9-coordinate geometry to one Lu(1), two equivalent Lu(2), and six equivalent Cu(1) atoms. In the second Ge site, Ge(2) is bonded in a 9-coordinate geometry to two equivalent Lu(1), four equivalent Lu(2), two equivalent Cu(1), and one Ge(2) atom.
Lu3(CuGe)4 crystallizes in the orthorhombic Immm space group. There are two inequivalent Lu sites. In the first Lu site, Lu(1) is bonded to two equivalent Ge(1) and four equivalent Ge(2) atoms to form distorted edge-sharing LuGe6 octahedra. Both Lu(1)-Ge(1) bond lengths are 2.93 Å. All Lu(1)-Ge(2) bond lengths are 2.88 Å. In the second Lu site, Lu(2) is bonded in a 12-coordinate geometry to six equivalent Cu(1), two equivalent Ge(1), and four equivalent Ge(2) atoms. There are four shorter (2.93 Å) and two longer (3.02 Å) Lu(2)-Cu(1) bond lengths. Both Lu(2)-Ge(1) bond lengths are 2.96 Å. All Lu(2)-Ge(2) bond lengths are 2.99 Å. Cu(1) is bonded in a 8-coordinate geometry to three equivalent Lu(2), one Cu(1), one Ge(2), and three equivalent Ge(1) atoms. The Cu(1)-Cu(1) bond length is 2.50 Å. The Cu(1)-Ge(2) bond length is 2.43 Å. There are two shorter (2.49 Å) and one longer (2.57 Å) Cu(1)-Ge(1) bond length. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded in a 9-coordinate geometry to one Lu(1), two equivalent Lu(2), and six equivalent Cu(1) atoms. In the second Ge site, Ge(2) is bonded in a 9-coordinate geometry to two equivalent Lu(1), four equivalent Lu(2), two equivalent Cu(1), and one Ge(2) atom. The Ge(2)-Ge(2) bond length is 2.51 Å.