UMnAl is Frank-Kasper $\mu$ Phase-derived structured and crystallizes in the monoclinic Pm space group. There are two inequivalent U sites. In the first U site, U(1) is bonded in a 15-coordinate geometry to three equivalent U(2), one Mn(1), one Mn(2), three equivalent Mn(3), one Al(4), two equivalent Al(1), two equivalent Al(2), and two equivalent Al(3) atoms. In the second U site, U(2) is bonded in a 16-coordinate geometry to one U(2), three equivalent U(1), two equivalent Mn(1), two equivalent Mn(2), three equivalent Mn(3), one Al(1), one Al(2), one Al(3), and two equivalent Al(4) atoms. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent U(1), four equivalent U(2), two equivalent Mn(2), two equivalent Mn(3), and two equivalent Al(4) atoms to form MnU6Mn4Al2 cuboctahedra that share corners with two equivalent Al(2)U6Mn2Al4 cuboctahedra, corners with four equivalent Mn(3)U6Mn2Al4 cuboctahedra, corners with four equivalent Mn(1)U6Mn4Al2 cuboctahedra, corners with four equivalent Al(1)U6Mn2Al4 cuboctahedra, corners with four equivalent Al(3)U6Mn2Al4 cuboctahedra, edges with two equivalent Mn(1)U6Mn4Al2 cuboctahedra, edges with four equivalent Al(2)U6Mn2Al4 cuboctahedra, faces with two equivalent Al(1)U6Mn2Al4 cuboctahedra, faces with two equivalent Al(3)U6Mn2Al4 cuboctahedra, faces with four equivalent Mn(2)U6Mn4Al2 cuboctahedra, faces with four equivalent Al(4)U6Mn6 cuboctahedra, and faces with six equivalent Mn(3)U6Mn2Al4 cuboctahedra. In the second Mn site, Mn(2) is bonded to two equivalent U(1), four equivalent U(2), two equivalent Mn(1), two equivalent Mn(3), and two equivalent Al(4) atoms to form MnU6Mn4Al2 cuboctahedra that share corners with two equivalent Al(3)U6Mn2Al4 cuboctahedra, corners with four equivalent Mn(3)U6Mn2Al4 cuboctahedra, corners with four equivalent Mn(2)U6Mn4Al2 cuboctahedra, corners with four equivalent Al(1)U6Mn2Al4 cuboctahedra, corners with four equivalent Al(2)U6Mn2Al4 cuboctahedra, edges with two equivalent Mn(2)U6Mn4Al2 cuboctahedra, edges with four equivalent Al(3)U6Mn2Al4 cuboctahedra, faces with two equivalent Al(1)U6Mn2Al4 cuboctahedra, faces with two equivalent Al(2)U6Mn2Al4 cuboctahedra, faces with four equivalent Mn(1)U6Mn4Al2 cuboctahedra, faces with four equivalent Al(4)U6Mn6 cuboctahedra, and faces with six equivalent Mn(3)U6Mn2Al4 cuboctahedra. In the third Mn site, Mn(3) is bonded to three equivalent U(1), three equivalent U(2), one Mn(1), one Mn(2), one Al(1), one Al(2), one Al(3), and one Al(4) atom to form MnU6Mn2Al4 cuboctahedra that share corners with two equivalent Mn(1)U6Mn4Al2 cuboctahedra, corners with two equivalent Mn(2)U6Mn4Al2 cuboctahedra, corners with two equivalent Al(1)U6Mn2Al4 cuboctahedra, corners with two equivalent Al(2)U6Mn2Al4 cuboctahedra, corners with two equivalent Al(3)U6Mn2Al4 cuboctahedra, corners with two equivalent Al(4)U6Mn6 cuboctahedra, edges with six equivalent Mn(3)U6Mn2Al4 cuboctahedra, faces with two equivalent Mn(3)U6Mn2Al4 cuboctahedra, faces with three equivalent Mn(1)U6Mn4Al2 cuboctahedra, faces with three equivalent Mn(2)U6Mn4Al2 cuboctahedra, faces with three equivalent Al(1)U6Mn2Al4 cuboctahedra, faces with three equivalent Al(2)U6Mn2Al4 cuboctahedra, faces with three equivalent Al(3)U6Mn2Al4 cuboctahedra, and faces with three equivalent Al(4)U6Mn6 cuboctahedra. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded to two equivalent U(2), four equivalent U(1), two equivalent Mn(3), two equivalent Al(2), and two equivalent Al(3) atoms to form AlU6Mn2Al4 cuboctahedra that share corners with two equivalent Al(4)U6Mn6 cuboctahedra, corners with four equivalent Mn(3)U6Mn2Al4 cuboctahedra, corners with four equivalent Mn(1)U6Mn4Al2 cuboctahedra, corners with four equivalent Mn(2)U6Mn4Al2 cuboctahedra, corners with four equivalent Al(1)U6Mn2Al4 cuboctahedra, edges with two equivalent Al(1)U6Mn2Al4 cuboctahedra, edges with four equivalent Al(4)U6Mn6 cuboctahedra, faces with two equivalent Mn(1)U6Mn4Al2 cuboctahedra, faces with two equivalent Mn(2)U6Mn4Al2 cuboctahedra, faces with four equivalent Al(2)U6Mn2Al4 cuboctahedra, faces with four equivalent Al(3)U6Mn2Al4 cuboctahedra, and faces with six equivalent Mn(3)U6Mn2Al4 cuboctahedra. In the second Al site, Al(2) is bonded to two equivalent U(2), four equivalent U(1), two equivalent Mn(3), two equivalent Al(1), and two equivalent Al(3) atoms to form AlU6Mn2Al4 cuboctahedra that share corners with two equivalent Mn(1)U6Mn4Al2 cuboctahedra, corners with four equivalent Mn(3)U6Mn2Al4 cuboctahedra, corners with four equivalent Mn(2)U6Mn4Al2 cuboctahedra, corners with four equivalent Al(2)U6Mn2Al4 cuboctahedra, corners with four equivalent Al(4)U6Mn6 cuboctahedra, edges with two equivalent Al(2)U6Mn2Al4 cuboctahedra, edges with four equivalent Mn(1)U6Mn4Al2 cuboctahedra, faces with two equivalent Mn(2)U6Mn4Al2 cuboctahedra, faces with two equivalent Al(4)U6Mn6 cuboctahedra, faces with four equivalent Al(1)U6Mn2Al4 cuboctahedra, faces with four equivalent Al(3)U6Mn2Al4 cuboctahedra, and faces with six equivalent Mn(3)U6Mn2Al4 cuboctahedra. In the third Al site, Al(3) is bonded to two equivalent U(2), four equivalent U(1), two equivalent Mn(3), two equivalent Al(1), and two equivalent Al(2) atoms to form AlU6Mn2Al4 cuboctahedra that share corners with two equivalent Mn(2)U6Mn4Al2 cuboctahedra, corners with four equivalent Mn(3)U6Mn2Al4 cuboctahedra, corners with four equivalent Mn(1)U6Mn4Al2 cuboctahedra, corners with four equivalent Al(3)U6Mn2Al4 cuboctahedra, corners with four equivalent Al(4)U6Mn6 cuboctahedra, edges with two equivalent Al(3)U6Mn2Al4 cuboctahedra, edges with four equivalent Mn(2)U6Mn4Al2 cuboctahedra, faces with two equivalent Mn(1)U6Mn4Al2 cuboctahedra, faces with two equivalent Al(4)U6Mn6 cuboctahedra, faces with four equivalent Al(1)U6Mn2Al4 cuboctahedra, faces with four equivalent Al(2)U6Mn2Al4 cuboctahedra, and faces with six equivalent Mn(3)U6Mn2Al4 cuboctahedra. In the fourth Al site, Al(4) is bonded to two equivalent U(1), four equivalent U(2), two equivalent Mn(1), two equivalent Mn(2), and two equivalent Mn(3) atoms to form AlU6Mn6 cuboctahedra that share corners with two equivalent Al(1)U6Mn2Al4 cuboctahedra, corners with four equivalent Mn(3)U6Mn2Al4 cuboctahedra, corners with four equivalent Al(2)U6Mn2Al4 cuboctahedra, corners with four equivalent Al(3)U6Mn2Al4 cuboctahedra, corners with four equivalent Al(4)U6Mn6 cuboctahedra, edges with two equivalent Al(4)U6Mn6 cuboctahedra, edges with four equivalent Al(1)U6Mn2Al4 cuboctahedra, faces with two equivalent Al(2)U6Mn2Al4 cuboctahedra, faces with two equivalent Al(3)U6Mn2Al4 cuboctahedra, faces with four equivalent Mn(1)U6Mn4Al2 cuboctahedra, faces with four equivalent Mn(2)U6Mn4Al2 cuboctahedra, and faces with six equivalent Mn(3)U6Mn2Al4 cuboctahedra.
UMnAl is Frank-Kasper $\mu$ Phase-derived structured and crystallizes in the monoclinic Pm space group. There are two inequivalent U sites. In the first U site, U(1) is bonded in a 15-coordinate geometry to three equivalent U(2), one Mn(1), one Mn(2), three equivalent Mn(3), one Al(4), two equivalent Al(1), two equivalent Al(2), and two equivalent Al(3) atoms. There are a spread of U(1)-U(2) bond distances ranging from 2.83-3.20 Å. The U(1)-Mn(1) bond length is 2.81 Å. The U(1)-Mn(2) bond length is 2.82 Å. There are two shorter (2.94 Å) and one longer (3.04 Å) U(1)-Mn(3) bond length. The U(1)-Al(4) bond length is 2.97 Å. Both U(1)-Al(1) bond lengths are 3.24 Å. There is one shorter (3.15 Å) and one longer (3.25 Å) U(1)-Al(2) bond length. There is one shorter (3.15 Å) and one longer (3.25 Å) U(1)-Al(3) bond length. In the second U site, U(2) is bonded in a 16-coordinate geometry to one U(2), three equivalent U(1), two equivalent Mn(1), two equivalent Mn(2), three equivalent Mn(3), one Al(1), one Al(2), one Al(3), and two equivalent Al(4) atoms. The U(2)-U(2) bond length is 3.26 Å. There is one shorter (3.02 Å) and one longer (3.03 Å) U(2)-Mn(1) bond length. There is one shorter (3.02 Å) and one longer (3.04 Å) U(2)-Mn(2) bond length. There are two shorter (2.99 Å) and one longer (3.08 Å) U(2)-Mn(3) bond length. The U(2)-Al(1) bond length is 3.17 Å. The U(2)-Al(2) bond length is 3.10 Å. The U(2)-Al(3) bond length is 3.10 Å. Both U(2)-Al(4) bond lengths are 3.07 Å. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent U(1), four equivalent U(2), two equivalent Mn(2), two equivalent Mn(3), and two equivalent Al(4) atoms to form MnU6Mn4Al2 cuboctahedra that share corners with two equivalent Al(2)U6Mn2Al4 cuboctahedra, corners with four equivalent Mn(3)U6Mn2Al4 cuboctahedra, corners with four equivalent Mn(1)U6Mn4Al2 cuboctahedra, corners with four equivalent Al(1)U6Mn2Al4 cuboctahedra, corners with four equivalent Al(3)U6Mn2Al4 cuboctahedra, edges with two equivalent Mn(1)U6Mn4Al2 cuboctahedra, edges with four equivalent Al(2)U6Mn2Al4 cuboctahedra, faces with two equivalent Al(1)U6Mn2Al4 cuboctahedra, faces with two equivalent Al(3)U6Mn2Al4 cuboctahedra, faces with four equivalent Mn(2)U6Mn4Al2 cuboctahedra, faces with four equivalent Al(4)U6Mn6 cuboctahedra, and faces with six equivalent Mn(3)U6Mn2Al4 cuboctahedra. There is one shorter (2.57 Å) and one longer (2.63 Å) Mn(1)-Mn(2) bond length. Both Mn(1)-Mn(3) bond lengths are 2.68 Å. There is one shorter (2.53 Å) and one longer (2.57 Å) Mn(1)-Al(4) bond length. In the second Mn site, Mn(2) is bonded to two equivalent U(1), four equivalent U(2), two equivalent Mn(1), two equivalent Mn(3), and two equivalent Al(4) atoms to form MnU6Mn4Al2 cuboctahedra that share corners with two equivalent Al(3)U6Mn2Al4 cuboctahedra, corners with four equivalent Mn(3)U6Mn2Al4 cuboctahedra, corners with four equivalent Mn(2)U6Mn4Al2 cuboctahedra, corners with four equivalent Al(1)U6Mn2Al4 cuboctahedra, corners with four equivalent Al(2)U6Mn2Al4 cuboctahedra, edges with two equivalent Mn(2)U6Mn4Al2 cuboctahedra, edges with four equivalent Al(3)U6Mn2Al4 cuboctahedra, faces with two equivalent Al(1)U6Mn2Al4 cuboctahedra, faces with two equivalent Al(2)U6Mn2Al4 cuboctahedra, faces with four equivalent Mn(1)U6Mn4Al2 cuboctahedra, faces with four equivalent Al(4)U6Mn6 cuboctahedra, and faces with six equivalent Mn(3)U6Mn2Al4 cuboctahedra. Both Mn(2)-Mn(3) bond lengths are 2.68 Å. There is one shorter (2.53 Å) and one longer (2.57 Å) Mn(2)-Al(4) bond length. In the third Mn site, Mn(3) is bonded to three equivalent U(1), three equivalent U(2), one Mn(1), one Mn(2), one Al(1), one Al(2), one Al(3), and one Al(4) atom to form MnU6Mn2Al4 cuboctahedra that share corners with two equivalent Mn(1)U6Mn4Al2 cuboctahedra, corners with two equivalent Mn(2)U6Mn4Al2 cuboctahedra, corners with two equivalent Al(1)U6Mn2Al4 cuboctahedra, corners with two equivalent Al(2)U6Mn2Al4 cuboctahedra, corners with two equivalent Al(3)U6Mn2Al4 cuboctahedra, corners with two equivalent Al(4)U6Mn6 cuboctahedra, edges with six equivalent Mn(3)U6Mn2Al4 cuboctahedra, faces with two equivalent Mn(3)U6Mn2Al4 cuboctahedra, faces with three equivalent Mn(1)U6Mn4Al2 cuboctahedra, faces with three equivalent Mn(2)U6Mn4Al2 cuboctahedra, faces with three equivalent Al(1)U6Mn2Al4 cuboctahedra, faces with three equivalent Al(2)U6Mn2Al4 cuboctahedra, faces with three equivalent Al(3)U6Mn2Al4 cuboctahedra, and faces with three equivalent Al(4)U6Mn6 cuboctahedra. The Mn(3)-Al(1) bond length is 2.60 Å. The Mn(3)-Al(2) bond length is 2.64 Å. The Mn(3)-Al(3) bond length is 2.64 Å. The Mn(3)-Al(4) bond length is 2.57 Å. There are four inequivalent Al sites. In the first Al site, Al(1) is bonded to two equivalent U(2), four equivalent U(1), two equivalent Mn(3), two equivalent Al(2), and two equivalent Al(3) atoms to form AlU6Mn2Al4 cuboctahedra that share corners with two equivalent Al(4)U6Mn6 cuboctahedra, corners with four equivalent Mn(3)U6Mn2Al4 cuboctahedra, corners with four equivalent Mn(1)U6Mn4Al2 cuboctahedra, corners with four equivalent Mn(2)U6Mn4Al2 cuboctahedra, corners with four equivalent Al(1)U6Mn2Al4 cuboctahedra, edges with two equivalent Al(1)U6Mn2Al4 cuboctahedra, edges with four equivalent Al(4)U6Mn6 cuboctahedra, faces with two equivalent Mn(1)U6Mn4Al2 cuboctahedra, faces with two equivalent Mn(2)U6Mn4Al2 cuboctahedra, faces with four equivalent Al(2)U6Mn2Al4 cuboctahedra, faces with four equivalent Al(3)U6Mn2Al4 cuboctahedra, and faces with six equivalent Mn(3)U6Mn2Al4 cuboctahedra. There is one shorter (2.54 Å) and one longer (2.57 Å) Al(1)-Al(2) bond length. There is one shorter (2.53 Å) and one longer (2.56 Å) Al(1)-Al(3) bond length. In the second Al site, Al(2) is bonded to two equivalent U(2), four equivalent U(1), two equivalent Mn(3), two equivalent Al(1), and two equivalent Al(3) atoms to form AlU6Mn2Al4 cuboctahedra that share corners with two equivalent Mn(1)U6Mn4Al2 cuboctahedra, corners with four equivalent Mn(3)U6Mn2Al4 cuboctahedra, corners with four equivalent Mn(2)U6Mn4Al2 cuboctahedra, corners with four equivalent Al(2)U6Mn2Al4 cuboctahedra, corners with four equivalent Al(4)U6Mn6 cuboctahedra, edges with two equivalent Al(2)U6Mn2Al4 cuboctahedra, edges with four equivalent Mn(1)U6Mn4Al2 cuboctahedra, faces with two equivalent Mn(2)U6Mn4Al2 cuboctahedra, faces with two equivalent Al(4)U6Mn6 cuboctahedra, faces with four equivalent Al(1)U6Mn2Al4 cuboctahedra, faces with four equivalent Al(3)U6Mn2Al4 cuboctahedra, and faces with six equivalent Mn(3)U6Mn2Al4 cuboctahedra. There is one shorter (2.56 Å) and one longer (2.64 Å) Al(2)-Al(3) bond length. In the third Al site, Al(3) is bonded to two equivalent U(2), four equivalent U(1), two equivalent Mn(3), two equivalent Al(1), and two equivalent Al(2) atoms to form AlU6Mn2Al4 cuboctahedra that share corners with two equivalent Mn(2)U6Mn4Al2 cuboctahedra, corners with four equivalent Mn(3)U6Mn2Al4 cuboctahedra, corners with four equivalent Mn(1)U6Mn4Al2 cuboctahedra, corners with four equivalent Al(3)U6Mn2Al4 cuboctahedra, corners with four equivalent Al(4)U6Mn6 cuboctahedra, edges with two equivalent Al(3)U6Mn2Al4 cuboctahedra, edges with four equivalent Mn(2)U6Mn4Al2 cuboctahedra, faces with two equivalent Mn(1)U6Mn4Al2 cuboctahedra, faces with two equivalent Al(4)U6Mn6 cuboctahedra, faces with four equivalent Al(1)U6Mn2Al4 cuboctahedra, faces with four equivalent Al(2)U6Mn2Al4 cuboctahedra, and faces with six equivalent Mn(3)U6Mn2Al4 cuboctahedra. In the fourth Al site, Al(4) is bonded to two equivalent U(1), four equivalent U(2), two equivalent Mn(1), two equivalent Mn(2), and two equivalent Mn(3) atoms to form AlU6Mn6 cuboctahedra that share corners with two equivalent Al(1)U6Mn2Al4 cuboctahedra, corners with four equivalent Mn(3)U6Mn2Al4 cuboctahedra, corners with four equivalent Al(2)U6Mn2Al4 cuboctahedra, corners with four equivalent Al(3)U6Mn2Al4 cuboctahedra, corners with four equivalent Al(4)U6Mn6 cuboctahedra, edges with two equivalent Al(4)U6Mn6 cuboctahedra, edges with four equivalent Al(1)U6Mn2Al4 cuboctahedra, faces with two equivalent Al(2)U6Mn2Al4 cuboctahedra, faces with two equivalent Al(3)U6Mn2Al4 cuboctahedra, faces with four equivalent Mn(1)U6Mn4Al2 cuboctahedra, faces with four equivalent Mn(2)U6Mn4Al2 cuboctahedra, and faces with six equivalent Mn(3)U6Mn2Al4 cuboctahedra.