Ni5Al3 crystallizes in the orthorhombic Cmmm space group. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to four equivalent Ni(2), four equivalent Ni(3), and four equivalent Al(2) atoms to form distorted NiAl4Ni8 cuboctahedra that share corners with four equivalent Ni(1)Al4Ni8 cuboctahedra, edges with eight equivalent Ni(2)Al6Ni6 cuboctahedra, faces with two equivalent Ni(1)Al4Ni8 cuboctahedra, and faces with four equivalent Ni(2)Al6Ni6 cuboctahedra. In the second Ni site, Ni(2) is bonded to two equivalent Ni(1), four equivalent Ni(3), two equivalent Al(1), and four equivalent Al(2) atoms to form distorted NiAl6Ni6 cuboctahedra that share corners with twelve equivalent Ni(2)Al6Ni6 cuboctahedra, edges with four equivalent Ni(1)Al4Ni8 cuboctahedra, faces with two equivalent Ni(1)Al4Ni8 cuboctahedra, and faces with six equivalent Ni(2)Al6Ni6 cuboctahedra. In the third Ni site, Ni(3) is bonded in a 6-coordinate geometry to two equivalent Ni(1), four equivalent Ni(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 body-centered cubic geometry to four equivalent Ni(2) and four equivalent Ni(3) atoms. In the second Al site, Al(2) is bonded in a 10-coordinate geometry to two equivalent Ni(1), four equivalent Ni(2), and four equivalent Ni(3) atoms.
Ni5Al3 crystallizes in the orthorhombic Cmmm space group. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to four equivalent Ni(2), four equivalent Ni(3), and four equivalent Al(2) atoms to form distorted NiAl4Ni8 cuboctahedra that share corners with four equivalent Ni(1)Al4Ni8 cuboctahedra, edges with eight equivalent Ni(2)Al6Ni6 cuboctahedra, faces with two equivalent Ni(1)Al4Ni8 cuboctahedra, and faces with four equivalent Ni(2)Al6Ni6 cuboctahedra. All Ni(1)-Ni(2) bond lengths are 2.47 Å. All Ni(1)-Ni(3) bond lengths are 2.60 Å. All Ni(1)-Al(2) bond lengths are 2.48 Å. In the second Ni site, Ni(2) is bonded to two equivalent Ni(1), four equivalent Ni(3), two equivalent Al(1), and four equivalent Al(2) atoms to form distorted NiAl6Ni6 cuboctahedra that share corners with twelve equivalent Ni(2)Al6Ni6 cuboctahedra, edges with four equivalent Ni(1)Al4Ni8 cuboctahedra, faces with two equivalent Ni(1)Al4Ni8 cuboctahedra, and faces with six equivalent Ni(2)Al6Ni6 cuboctahedra. All Ni(2)-Ni(3) bond lengths are 2.63 Å. Both Ni(2)-Al(1) bond lengths are 2.47 Å. All Ni(2)-Al(2) bond lengths are 2.49 Å. In the third Ni site, Ni(3) is bonded in a 6-coordinate geometry to two equivalent Ni(1), four equivalent Ni(2), two equivalent Al(1), and four equivalent Al(2) atoms. Both Ni(3)-Al(1) bond lengths are 2.37 Å. There are two shorter (2.44 Å) and two longer (2.53 Å) Ni(3)-Al(2) bond lengths. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a body-centered cubic geometry to four equivalent Ni(2) and four equivalent Ni(3) atoms. In the second Al site, Al(2) is bonded in a 10-coordinate geometry to two equivalent Ni(1), four equivalent Ni(2), and four equivalent Ni(3) atoms.