YNiAl crystallizes in the orthorhombic Amm2 space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 12-coordinate geometry to three equivalent Y(2), two equivalent Ni(1), three equivalent Ni(2), one Al(3), two equivalent Al(1), and four equivalent Al(2) atoms. In the second Y site, Y(2) is bonded in a 16-coordinate geometry to one Y(2), three equivalent Y(1), three equivalent Ni(2), four equivalent Ni(1), one Al(1), two equivalent Al(2), and two equivalent Al(3) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent Y(1), four equivalent Y(2), two equivalent Ni(1), two equivalent Ni(2), and two equivalent Al(3) atoms to form distorted NiY6Al2Ni4 cuboctahedra that share corners with four equivalent Ni(1)Y6Al2Ni4 cuboctahedra, corners with four equivalent Ni(2)Y6Al4Ni2 cuboctahedra, corners with four equivalent Al(1)Y6Al4Ni2 cuboctahedra, corners with six equivalent Al(2)Y6Al4Ni2 cuboctahedra, edges with two equivalent Ni(1)Y6Al2Ni4 cuboctahedra, edges with four equivalent Al(2)Y6Al4Ni2 cuboctahedra, faces with two equivalent Al(1)Y6Al4Ni2 cuboctahedra, faces with two equivalent Al(2)Y6Al4Ni2 cuboctahedra, faces with four equivalent Ni(1)Y6Al2Ni4 cuboctahedra, faces with four equivalent Al(3)Y6Ni6 cuboctahedra, and faces with six equivalent Ni(2)Y6Al4Ni2 cuboctahedra. In the second Ni site, Ni(2) is bonded to three equivalent Y(1), three equivalent Y(2), two equivalent Ni(1), one Al(1), one Al(3), and two equivalent Al(2) atoms to form distorted NiY6Al4Ni2 cuboctahedra that share corners with two equivalent Al(1)Y6Al4Ni2 cuboctahedra, corners with two equivalent Al(3)Y6Ni6 cuboctahedra, corners with four equivalent Ni(1)Y6Al2Ni4 cuboctahedra, corners with four equivalent Al(2)Y6Al4Ni2 cuboctahedra, edges with six equivalent Ni(2)Y6Al4Ni2 cuboctahedra, faces with two equivalent Ni(2)Y6Al4Ni2 cuboctahedra, faces with three equivalent Al(1)Y6Al4Ni2 cuboctahedra, faces with three equivalent Al(3)Y6Ni6 cuboctahedra, faces with six equivalent Ni(1)Y6Al2Ni4 cuboctahedra, and faces with six equivalent Al(2)Y6Al4Ni2 cuboctahedra. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to two equivalent Y(2), four equivalent Y(1), two equivalent Ni(2), and four equivalent Al(2) atoms to form distorted AlY6Al4Ni2 cuboctahedra that share corners with two equivalent Al(3)Y6Ni6 cuboctahedra, corners with four equivalent Ni(2)Y6Al4Ni2 cuboctahedra, corners with four equivalent Al(1)Y6Al4Ni2 cuboctahedra, corners with eight equivalent Ni(1)Y6Al2Ni4 cuboctahedra, edges with two equivalent Al(1)Y6Al4Ni2 cuboctahedra, edges with four equivalent Al(3)Y6Ni6 cuboctahedra, faces with four equivalent Ni(1)Y6Al2Ni4 cuboctahedra, faces with six equivalent Ni(2)Y6Al4Ni2 cuboctahedra, and faces with eight equivalent Al(2)Y6Al4Ni2 cuboctahedra. In the second Al site, Al(2) is bonded to two equivalent Y(2), four equivalent Y(1), two equivalent Ni(2), two equivalent Al(1), and two equivalent Al(2) atoms to form distorted AlY6Al4Ni2 cuboctahedra that share corners with four equivalent Ni(2)Y6Al4Ni2 cuboctahedra, corners with four equivalent Al(2)Y6Al4Ni2 cuboctahedra, corners with four equivalent Al(3)Y6Ni6 cuboctahedra, corners with six equivalent Ni(1)Y6Al2Ni4 cuboctahedra, edges with two equivalent Al(2)Y6Al4Ni2 cuboctahedra, edges with four equivalent Ni(1)Y6Al2Ni4 cuboctahedra, faces with two equivalent Ni(1)Y6Al2Ni4 cuboctahedra, faces with two equivalent Al(3)Y6Ni6 cuboctahedra, faces with four equivalent Al(1)Y6Al4Ni2 cuboctahedra, faces with four equivalent Al(2)Y6Al4Ni2 cuboctahedra, and faces with six equivalent Ni(2)Y6Al4Ni2 cuboctahedra. In the third Al site, Al(3) is bonded to two equivalent Y(1), four equivalent Y(2), two equivalent Ni(2), and four equivalent Ni(1) atoms to form distorted AlY6Ni6 cuboctahedra that share corners with two equivalent Al(1)Y6Al4Ni2 cuboctahedra, corners with four equivalent Ni(2)Y6Al4Ni2 cuboctahedra, corners with four equivalent Al(3)Y6Ni6 cuboctahedra, corners with eight equivalent Al(2)Y6Al4Ni2 cuboctahedra, edges with two equivalent Al(3)Y6Ni6 cuboctahedra, edges with four equivalent Al(1)Y6Al4Ni2 cuboctahedra, faces with four equivalent Al(2)Y6Al4Ni2 cuboctahedra, faces with six equivalent Ni(2)Y6Al4Ni2 cuboctahedra, and faces with eight equivalent Ni(1)Y6Al2Ni4 cuboctahedra.
YNiAl crystallizes in the orthorhombic Amm2 space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 12-coordinate geometry to three equivalent Y(2), two equivalent Ni(1), three equivalent Ni(2), one Al(3), two equivalent Al(1), and four equivalent Al(2) atoms. There is one shorter (3.15 Å) and two longer (3.25 Å) Y(1)-Y(2) bond lengths. Both Y(1)-Ni(1) bond lengths are 2.95 Å. There is one shorter (3.04 Å) and two longer (3.11 Å) Y(1)-Ni(2) bond lengths. The Y(1)-Al(3) bond length is 3.07 Å. Both Y(1)-Al(1) bond lengths are 3.23 Å. There are two shorter (3.17 Å) and two longer (3.20 Å) Y(1)-Al(2) bond lengths. In the second Y site, Y(2) is bonded in a 16-coordinate geometry to one Y(2), three equivalent Y(1), three equivalent Ni(2), four equivalent Ni(1), one Al(1), two equivalent Al(2), and two equivalent Al(3) atoms. The Y(2)-Y(2) bond length is 3.14 Å. There is one shorter (3.13 Å) and two longer (3.15 Å) Y(2)-Ni(2) bond lengths. There are two shorter (3.00 Å) and two longer (3.14 Å) Y(2)-Ni(1) bond lengths. The Y(2)-Al(1) bond length is 3.13 Å. Both Y(2)-Al(2) bond lengths are 3.16 Å. Both Y(2)-Al(3) bond lengths are 3.12 Å. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent Y(1), four equivalent Y(2), two equivalent Ni(1), two equivalent Ni(2), and two equivalent Al(3) atoms to form distorted NiY6Al2Ni4 cuboctahedra that share corners with four equivalent Ni(1)Y6Al2Ni4 cuboctahedra, corners with four equivalent Ni(2)Y6Al4Ni2 cuboctahedra, corners with four equivalent Al(1)Y6Al4Ni2 cuboctahedra, corners with six equivalent Al(2)Y6Al4Ni2 cuboctahedra, edges with two equivalent Ni(1)Y6Al2Ni4 cuboctahedra, edges with four equivalent Al(2)Y6Al4Ni2 cuboctahedra, faces with two equivalent Al(1)Y6Al4Ni2 cuboctahedra, faces with two equivalent Al(2)Y6Al4Ni2 cuboctahedra, faces with four equivalent Ni(1)Y6Al2Ni4 cuboctahedra, faces with four equivalent Al(3)Y6Ni6 cuboctahedra, and faces with six equivalent Ni(2)Y6Al4Ni2 cuboctahedra. There is one shorter (2.62 Å) and one longer (2.77 Å) Ni(1)-Ni(1) bond length. Both Ni(1)-Ni(2) bond lengths are 2.73 Å. There is one shorter (2.52 Å) and one longer (2.76 Å) Ni(1)-Al(3) bond length. In the second Ni site, Ni(2) is bonded to three equivalent Y(1), three equivalent Y(2), two equivalent Ni(1), one Al(1), one Al(3), and two equivalent Al(2) atoms to form distorted NiY6Al4Ni2 cuboctahedra that share corners with two equivalent Al(1)Y6Al4Ni2 cuboctahedra, corners with two equivalent Al(3)Y6Ni6 cuboctahedra, corners with four equivalent Ni(1)Y6Al2Ni4 cuboctahedra, corners with four equivalent Al(2)Y6Al4Ni2 cuboctahedra, edges with six equivalent Ni(2)Y6Al4Ni2 cuboctahedra, faces with two equivalent Ni(2)Y6Al4Ni2 cuboctahedra, faces with three equivalent Al(1)Y6Al4Ni2 cuboctahedra, faces with three equivalent Al(3)Y6Ni6 cuboctahedra, faces with six equivalent Ni(1)Y6Al2Ni4 cuboctahedra, and faces with six equivalent Al(2)Y6Al4Ni2 cuboctahedra. The Ni(2)-Al(1) bond length is 2.58 Å. The Ni(2)-Al(3) bond length is 2.58 Å. Both Ni(2)-Al(2) bond lengths are 2.56 Å. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to two equivalent Y(2), four equivalent Y(1), two equivalent Ni(2), and four equivalent Al(2) atoms to form distorted AlY6Al4Ni2 cuboctahedra that share corners with two equivalent Al(3)Y6Ni6 cuboctahedra, corners with four equivalent Ni(2)Y6Al4Ni2 cuboctahedra, corners with four equivalent Al(1)Y6Al4Ni2 cuboctahedra, corners with eight equivalent Ni(1)Y6Al2Ni4 cuboctahedra, edges with two equivalent Al(1)Y6Al4Ni2 cuboctahedra, edges with four equivalent Al(3)Y6Ni6 cuboctahedra, faces with four equivalent Ni(1)Y6Al2Ni4 cuboctahedra, faces with six equivalent Ni(2)Y6Al4Ni2 cuboctahedra, and faces with eight equivalent Al(2)Y6Al4Ni2 cuboctahedra. There are two shorter (2.63 Å) and two longer (2.65 Å) Al(1)-Al(2) bond lengths. In the second Al site, Al(2) is bonded to two equivalent Y(2), four equivalent Y(1), two equivalent Ni(2), two equivalent Al(1), and two equivalent Al(2) atoms to form distorted AlY6Al4Ni2 cuboctahedra that share corners with four equivalent Ni(2)Y6Al4Ni2 cuboctahedra, corners with four equivalent Al(2)Y6Al4Ni2 cuboctahedra, corners with four equivalent Al(3)Y6Ni6 cuboctahedra, corners with six equivalent Ni(1)Y6Al2Ni4 cuboctahedra, edges with two equivalent Al(2)Y6Al4Ni2 cuboctahedra, edges with four equivalent Ni(1)Y6Al2Ni4 cuboctahedra, faces with two equivalent Ni(1)Y6Al2Ni4 cuboctahedra, faces with two equivalent Al(3)Y6Ni6 cuboctahedra, faces with four equivalent Al(1)Y6Al4Ni2 cuboctahedra, faces with four equivalent Al(2)Y6Al4Ni2 cuboctahedra, and faces with six equivalent Ni(2)Y6Al4Ni2 cuboctahedra. There is one shorter (2.66 Å) and one longer (2.73 Å) Al(2)-Al(2) bond length. In the third Al site, Al(3) is bonded to two equivalent Y(1), four equivalent Y(2), two equivalent Ni(2), and four equivalent Ni(1) atoms to form distorted AlY6Ni6 cuboctahedra that share corners with two equivalent Al(1)Y6Al4Ni2 cuboctahedra, corners with four equivalent Ni(2)Y6Al4Ni2 cuboctahedra, corners with four equivalent Al(3)Y6Ni6 cuboctahedra, corners with eight equivalent Al(2)Y6Al4Ni2 cuboctahedra, edges with two equivalent Al(3)Y6Ni6 cuboctahedra, edges with four equivalent Al(1)Y6Al4Ni2 cuboctahedra, faces with four equivalent Al(2)Y6Al4Ni2 cuboctahedra, faces with six equivalent Ni(2)Y6Al4Ni2 cuboctahedra, and faces with eight equivalent Ni(1)Y6Al2Ni4 cuboctahedra.