UCu4Al8 crystallizes in the tetragonal I4/mmm space group. U(1) is bonded in a distorted square co-planar geometry to four equivalent Cu(1), eight equivalent Al(1), and eight equivalent Al(2) atoms. Cu(1) is bonded in a 10-coordinate geometry to one U(1), one Cu(1), four equivalent Al(1), and four equivalent Al(2) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 12-coordinate geometry to two equivalent U(1), four equivalent Cu(1), two equivalent Al(1), and four equivalent Al(2) atoms. In the second Al site, Al(2) is bonded in a 12-coordinate geometry to two equivalent U(1), four equivalent Cu(1), two equivalent Al(2), and four equivalent Al(1) atoms.
UCu4Al8 crystallizes in the tetragonal I4/mmm space group. U(1) is bonded in a distorted square co-planar geometry to four equivalent Cu(1), eight equivalent Al(1), and eight equivalent Al(2) atoms. All U(1)-Cu(1) bond lengths are 3.04 Å. All U(1)-Al(1) bond lengths are 3.36 Å. All U(1)-Al(2) bond lengths are 3.33 Å. Cu(1) is bonded in a 10-coordinate geometry to one U(1), one Cu(1), four equivalent Al(1), and four equivalent Al(2) atoms. The Cu(1)-Cu(1) bond length is 2.62 Å. All Cu(1)-Al(1) bond lengths are 2.70 Å. There are two shorter (2.74 Å) and two longer (2.91 Å) Cu(1)-Al(2) bond lengths. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 12-coordinate geometry to two equivalent U(1), four equivalent Cu(1), two equivalent Al(1), and four equivalent Al(2) atoms. Both Al(1)-Al(1) bond lengths are 2.70 Å. All Al(1)-Al(2) bond lengths are 2.57 Å. In the second Al site, Al(2) is bonded in a 12-coordinate geometry to two equivalent U(1), four equivalent Cu(1), two equivalent Al(2), and four equivalent Al(1) atoms. Both Al(2)-Al(2) bond lengths are 2.75 Å.