UIr crystallizes in the triclinic P-1 space group. There are four inequivalent U sites. In the first U site, U(1) is bonded in a 8-coordinate geometry to one U(4), two equivalent U(3), one Ir(1), one Ir(2), one Ir(4), and two equivalent Ir(3) atoms. In the second U site, U(2) is bonded in a 8-coordinate geometry to one U(4), one Ir(3), two equivalent Ir(1), two equivalent Ir(2), and two equivalent Ir(4) atoms. In the third U site, U(3) is bonded in a 5-coordinate geometry to one U(3), two equivalent U(1), one Ir(3), and one Ir(4) atom. In the fourth U site, U(4) is bonded in a 3-coordinate geometry to one U(1), one U(2), and one Ir(4) atom. There are four inequivalent Ir sites. In the first Ir site, Ir(1) is bonded in a 1-coordinate geometry to one U(1), two equivalent U(2), two equivalent Ir(2), two equivalent Ir(4), and three equivalent Ir(3) atoms. In the second Ir site, Ir(2) is bonded in a 10-coordinate geometry to one U(1), two equivalent U(2), one Ir(2), two equivalent Ir(1), two equivalent Ir(3), and two equivalent Ir(4) atoms. In the third Ir site, Ir(3) is bonded in a 11-coordinate geometry to one U(2), one U(3), two equivalent U(1), one Ir(3), one Ir(4), two equivalent Ir(2), and three equivalent Ir(1) atoms. In the fourth Ir site, Ir(4) is bonded in a 10-coordinate geometry to one U(1), one U(3), one U(4), two equivalent U(2), one Ir(3), two equivalent Ir(1), and two equivalent Ir(2) atoms.
UIr crystallizes in the triclinic P-1 space group. There are four inequivalent U sites. In the first U site, U(1) is bonded in a 8-coordinate geometry to one U(4), two equivalent U(3), one Ir(1), one Ir(2), one Ir(4), and two equivalent Ir(3) atoms. The U(1)-U(4) bond length is 2.59 Å. There is one shorter (2.66 Å) and one longer (2.78 Å) U(1)-U(3) bond length. The U(1)-Ir(1) bond length is 2.65 Å. The U(1)-Ir(2) bond length is 3.00 Å. The U(1)-Ir(4) bond length is 2.90 Å. There is one shorter (2.79 Å) and one longer (2.85 Å) U(1)-Ir(3) bond length. In the second U site, U(2) is bonded in a 8-coordinate geometry to one U(4), one Ir(3), two equivalent Ir(1), two equivalent Ir(2), and two equivalent Ir(4) atoms. The U(2)-U(4) bond length is 2.64 Å. The U(2)-Ir(3) bond length is 3.03 Å. There is one shorter (3.02 Å) and one longer (3.08 Å) U(2)-Ir(1) bond length. There is one shorter (2.83 Å) and one longer (3.10 Å) U(2)-Ir(2) bond length. There is one shorter (2.69 Å) and one longer (3.03 Å) U(2)-Ir(4) bond length. In the third U site, U(3) is bonded in a 5-coordinate geometry to one U(3), two equivalent U(1), one Ir(3), and one Ir(4) atom. The U(3)-U(3) bond length is 2.47 Å. The U(3)-Ir(3) bond length is 2.95 Å. The U(3)-Ir(4) bond length is 2.93 Å. In the fourth U site, U(4) is bonded in a 3-coordinate geometry to one U(1), one U(2), and one Ir(4) atom. The U(4)-Ir(4) bond length is 3.12 Å. There are four inequivalent Ir sites. In the first Ir site, Ir(1) is bonded in a 1-coordinate geometry to one U(1), two equivalent U(2), two equivalent Ir(2), two equivalent Ir(4), and three equivalent Ir(3) atoms. There is one shorter (2.68 Å) and one longer (2.77 Å) Ir(1)-Ir(2) bond length. There is one shorter (2.68 Å) and one longer (2.88 Å) Ir(1)-Ir(4) bond length. There are a spread of Ir(1)-Ir(3) bond distances ranging from 2.72-2.95 Å. In the second Ir site, Ir(2) is bonded in a 10-coordinate geometry to one U(1), two equivalent U(2), one Ir(2), two equivalent Ir(1), two equivalent Ir(3), and two equivalent Ir(4) atoms. The Ir(2)-Ir(2) bond length is 2.65 Å. Both Ir(2)-Ir(3) bond lengths are 2.67 Å. There is one shorter (2.76 Å) and one longer (2.77 Å) Ir(2)-Ir(4) bond length. In the third Ir site, Ir(3) is bonded in a 11-coordinate geometry to one U(2), one U(3), two equivalent U(1), one Ir(3), one Ir(4), two equivalent Ir(2), and three equivalent Ir(1) atoms. The Ir(3)-Ir(3) bond length is 2.82 Å. The Ir(3)-Ir(4) bond length is 2.65 Å. In the fourth Ir site, Ir(4) is bonded in a 10-coordinate geometry to one U(1), one U(3), one U(4), two equivalent U(2), one Ir(3), two equivalent Ir(1), and two equivalent Ir(2) atoms.