U3(CoAl3)4 crystallizes in the hexagonal P6_3/mmc space group. U(1) is bonded in a 17-coordinate geometry to two equivalent U(1), four equivalent Co(1), one Al(4), two equivalent Al(1), two equivalent Al(3), and six equivalent Al(2) atoms. There are two inequivalent Co sites. In the first Co site, Co(2) is bonded in a body-centered cubic geometry to two equivalent Al(4) and six equivalent Al(2) atoms. In the second Co site, Co(1) is bonded in a 8-coordinate geometry to four equivalent U(1), two equivalent Al(1), two equivalent Al(3), and four equivalent Al(2) atoms. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded in a 12-coordinate geometry to two equivalent U(1), two equivalent Co(1), two equivalent Al(1), two equivalent Al(3), and four equivalent Al(2) atoms. In the second Al site, Al(2) is bonded in a 3-coordinate geometry to three equivalent U(1), one Co(2), two equivalent Co(1), and two equivalent Al(1) atoms. In the third Al site, Al(3) is bonded in a 3-coordinate geometry to three equivalent U(1), three equivalent Co(1), and three equivalent Al(1) atoms. In the fourth Al site, Al(4) is bonded in a distorted linear geometry to three equivalent U(1) and two equivalent Co(2) atoms.
U3(CoAl3)4 crystallizes in the hexagonal P6_3/mmc space group. U(1) is bonded in a 17-coordinate geometry to two equivalent U(1), four equivalent Co(1), one Al(4), two equivalent Al(1), two equivalent Al(3), and six equivalent Al(2) atoms. Both U(1)-U(1) bond lengths are 3.25 Å. All U(1)-Co(1) bond lengths are 3.23 Å. The U(1)-Al(4) bond length is 3.07 Å. Both U(1)-Al(1) bond lengths are 2.92 Å. Both U(1)-Al(3) bond lengths are 2.96 Å. There are two shorter (3.14 Å) and four longer (3.21 Å) U(1)-Al(2) bond lengths. There are two inequivalent Co sites. In the first Co site, Co(2) is bonded in a body-centered cubic geometry to two equivalent Al(4) and six equivalent Al(2) atoms. Both Co(2)-Al(4) bond lengths are 2.33 Å. All Co(2)-Al(2) bond lengths are 2.48 Å. In the second Co site, Co(1) is bonded in a 8-coordinate geometry to four equivalent U(1), two equivalent Al(1), two equivalent Al(3), and four equivalent Al(2) atoms. Both Co(1)-Al(1) bond lengths are 2.49 Å. Both Co(1)-Al(3) bond lengths are 2.47 Å. All Co(1)-Al(2) bond lengths are 2.63 Å. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded in a 12-coordinate geometry to two equivalent U(1), two equivalent Co(1), two equivalent Al(1), two equivalent Al(3), and four equivalent Al(2) atoms. Both Al(1)-Al(1) bond lengths are 2.75 Å. Both Al(1)-Al(3) bond lengths are 2.85 Å. All Al(1)-Al(2) bond lengths are 2.77 Å. In the second Al site, Al(2) is bonded in a 3-coordinate geometry to three equivalent U(1), one Co(2), two equivalent Co(1), and two equivalent Al(1) atoms. In the third Al site, Al(3) is bonded in a 3-coordinate geometry to three equivalent U(1), three equivalent Co(1), and three equivalent Al(1) atoms. In the fourth Al site, Al(4) is bonded in a distorted linear geometry to three equivalent U(1) and two equivalent Co(2) atoms.