Hf6Ir7Al16 crystallizes in the cubic Fm-3m space group. Hf(1) is bonded in a 16-coordinate geometry to four equivalent Hf(1), four equivalent Ir(1), four equivalent Al(1), and four equivalent Al(2) atoms. There are two inequivalent Ir sites. In the first Ir site, Ir(1) is bonded to four equivalent Hf(1), four equivalent Al(1), and four equivalent Al(2) atoms to form distorted IrHf4Al8 cuboctahedra that share corners with four equivalent Ir(1)Hf4Al8 cuboctahedra, corners with eight equivalent Al(2)Hf3Ir4 tetrahedra, edges with four equivalent Al(2)Hf3Ir4 tetrahedra, and faces with eight equivalent Ir(1)Hf4Al8 cuboctahedra. In the second Ir site, Ir(2) is bonded in a body-centered cubic geometry to eight equivalent Al(2) atoms. There are two inequivalent Al sites. In the first Al site, Al(2) is bonded to three equivalent Hf(1), one Ir(2), and three equivalent Ir(1) atoms to form distorted AlHf3Ir4 tetrahedra that share corners with six equivalent Ir(1)Hf4Al8 cuboctahedra, corners with seven equivalent Al(2)Hf3Ir4 tetrahedra, edges with three equivalent Ir(1)Hf4Al8 cuboctahedra, edges with three equivalent Al(2)Hf3Ir4 tetrahedra, and faces with three equivalent Al(2)Hf3Ir4 tetrahedra. In the second Al site, Al(1) is bonded in a 6-coordinate geometry to three equivalent Hf(1) and three equivalent Ir(1) atoms.
Hf6Ir7Al16 crystallizes in the cubic Fm-3m space group. Hf(1) is bonded in a 16-coordinate geometry to four equivalent Hf(1), four equivalent Ir(1), four equivalent Al(1), and four equivalent Al(2) atoms. All Hf(1)-Hf(1) bond lengths are 3.21 Å. All Hf(1)-Ir(1) bond lengths are 3.16 Å. All Hf(1)-Al(1) bond lengths are 2.82 Å. All Hf(1)-Al(2) bond lengths are 3.16 Å. There are two inequivalent Ir sites. In the first Ir site, Ir(1) is bonded to four equivalent Hf(1), four equivalent Al(1), and four equivalent Al(2) atoms to form distorted IrHf4Al8 cuboctahedra that share corners with four equivalent Ir(1)Hf4Al8 cuboctahedra, corners with eight equivalent Al(2)Hf3Ir4 tetrahedra, edges with four equivalent Al(2)Hf3Ir4 tetrahedra, and faces with eight equivalent Ir(1)Hf4Al8 cuboctahedra. All Ir(1)-Al(1) bond lengths are 2.50 Å. All Ir(1)-Al(2) bond lengths are 2.69 Å. In the second Ir site, Ir(2) is bonded in a body-centered cubic geometry to eight equivalent Al(2) atoms. All Ir(2)-Al(2) bond lengths are 2.54 Å. There are two inequivalent Al sites. In the first Al site, Al(2) is bonded to three equivalent Hf(1), one Ir(2), and three equivalent Ir(1) atoms to form distorted AlHf3Ir4 tetrahedra that share corners with six equivalent Ir(1)Hf4Al8 cuboctahedra, corners with seven equivalent Al(2)Hf3Ir4 tetrahedra, edges with three equivalent Ir(1)Hf4Al8 cuboctahedra, edges with three equivalent Al(2)Hf3Ir4 tetrahedra, and faces with three equivalent Al(2)Hf3Ir4 tetrahedra. In the second Al site, Al(1) is bonded in a 6-coordinate geometry to three equivalent Hf(1) and three equivalent Ir(1) atoms.