GdAuAl4Ge2 crystallizes in the trigonal R-3m space group. Gd(1) is bonded to six equivalent Ge(1) atoms to form GdGe6 octahedra that share corners with six equivalent Al(2)Ge3Au tetrahedra, corners with six equivalent Al(1)GeAu3 tetrahedra, edges with six equivalent Gd(1)Ge6 octahedra, and edges with six equivalent Al(2)Ge3Au tetrahedra. Au(1) is bonded in a body-centered cubic geometry to two equivalent Al(2) and six equivalent Al(1) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to three equivalent Au(1) and one Ge(1) atom to form AlGeAu3 tetrahedra that share corners with three equivalent Gd(1)Ge6 octahedra, corners with three equivalent Al(2)Ge3Au tetrahedra, corners with nine equivalent Al(1)GeAu3 tetrahedra, edges with three equivalent Al(2)Ge3Au tetrahedra, and edges with three equivalent Al(1)GeAu3 tetrahedra. The corner-sharing octahedral tilt angles are 54°. In the second Al site, Al(2) is bonded to one Au(1) and three equivalent Ge(1) atoms to form AlGe3Au tetrahedra that share corners with three equivalent Gd(1)Ge6 octahedra, corners with three equivalent Al(1)GeAu3 tetrahedra, corners with seven equivalent Al(2)Ge3Au tetrahedra, edges with three equivalent Gd(1)Ge6 octahedra, and edges with three equivalent Al(1)GeAu3 tetrahedra. The corner-sharing octahedral tilt angles are 17°. Ge(1) is bonded to three equivalent Gd(1), one Al(1), and three equivalent Al(2) atoms to form a mixture of distorted edge and corner-sharing GeGd3Al4 pentagonal bipyramids.
GdAuAl4Ge2 crystallizes in the trigonal R-3m space group. Gd(1) is bonded to six equivalent Ge(1) atoms to form GdGe6 octahedra that share corners with six equivalent Al(2)Ge3Au tetrahedra, corners with six equivalent Al(1)GeAu3 tetrahedra, edges with six equivalent Gd(1)Ge6 octahedra, and edges with six equivalent Al(2)Ge3Au tetrahedra. All Gd(1)-Ge(1) bond lengths are 3.23 Å. Au(1) is bonded in a body-centered cubic geometry to two equivalent Al(2) and six equivalent Al(1) atoms. Both Au(1)-Al(2) bond lengths are 2.81 Å. All Au(1)-Al(1) bond lengths are 2.75 Å. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to three equivalent Au(1) and one Ge(1) atom to form AlGeAu3 tetrahedra that share corners with three equivalent Gd(1)Ge6 octahedra, corners with three equivalent Al(2)Ge3Au tetrahedra, corners with nine equivalent Al(1)GeAu3 tetrahedra, edges with three equivalent Al(2)Ge3Au tetrahedra, and edges with three equivalent Al(1)GeAu3 tetrahedra. The corner-sharing octahedral tilt angles are 54°. The Al(1)-Ge(1) bond length is 2.82 Å. In the second Al site, Al(2) is bonded to one Au(1) and three equivalent Ge(1) atoms to form AlGe3Au tetrahedra that share corners with three equivalent Gd(1)Ge6 octahedra, corners with three equivalent Al(1)GeAu3 tetrahedra, corners with seven equivalent Al(2)Ge3Au tetrahedra, edges with three equivalent Gd(1)Ge6 octahedra, and edges with three equivalent Al(1)GeAu3 tetrahedra. The corner-sharing octahedral tilt angles are 17°. All Al(2)-Ge(1) bond lengths are 2.76 Å. Ge(1) is bonded to three equivalent Gd(1), one Al(1), and three equivalent Al(2) atoms to form a mixture of distorted edge and corner-sharing GeGd3Al4 pentagonal bipyramids.