UCu6Al6 crystallizes in the orthorhombic Fmmm space group. U(1) is bonded in a 20-coordinate geometry to four equivalent Cu(1), four equivalent Cu(2), four equivalent Al(1), and eight equivalent Al(2) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(2) is bonded in a 4-coordinate geometry to two equivalent U(1), four equivalent Cu(1), and four equivalent Al(2) atoms. In the second Cu site, Cu(1) is bonded in a 10-coordinate geometry to one U(1), one Cu(1), two equivalent Cu(2), two 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), two equivalent Cu(2), four equivalent Cu(1), two equivalent Al(1), and two equivalent Al(2) atoms.
UCu6Al6 crystallizes in the orthorhombic Fmmm space group. U(1) is bonded in a 20-coordinate geometry to four equivalent Cu(1), four equivalent Cu(2), four equivalent Al(1), and eight equivalent Al(2) atoms. All U(1)-Cu(1) bond lengths are 3.04 Å. All U(1)-Cu(2) bond lengths are 3.31 Å. All U(1)-Al(1) bond lengths are 3.36 Å. All U(1)-Al(2) bond lengths are 3.23 Å. There are two inequivalent Cu sites. In the first Cu site, Cu(2) is bonded in a 4-coordinate geometry to two equivalent U(1), four equivalent Cu(1), and four equivalent Al(2) atoms. All Cu(2)-Cu(1) bond lengths are 2.70 Å. All Cu(2)-Al(2) bond lengths are 2.43 Å. In the second Cu site, Cu(1) is bonded in a 10-coordinate geometry to one U(1), one Cu(1), two equivalent Cu(2), two equivalent Al(1), and four equivalent Al(2) atoms. The Cu(1)-Cu(1) bond length is 2.64 Å. Both Cu(1)-Al(1) bond lengths are 2.62 Å. There are a spread of Cu(1)-Al(2) bond distances ranging from 2.64-2.73 Å. 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 2.51 Å. All Al(1)-Al(2) bond lengths are 2.61 Å. In the second Al site, Al(2) is bonded in a 12-coordinate geometry to two equivalent U(1), two equivalent Cu(2), four equivalent Cu(1), two equivalent Al(1), and two equivalent Al(2) atoms. There is one shorter (2.76 Å) and one longer (3.00 Å) Al(2)-Al(2) bond length.