NdNi4Al crystallizes in the orthorhombic Cmmm space group. Nd(1) is bonded in a 18-coordinate geometry to six equivalent Ni(1), eight equivalent Ni(2), and four equivalent Al(1) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 9-coordinate geometry to three equivalent Nd(1), four equivalent Ni(2), and two equivalent Al(1) atoms. In the second Ni site, Ni(2) is bonded to four equivalent Nd(1), two equivalent Ni(2), four equivalent Ni(1), and two equivalent Al(1) atoms to form a mixture of distorted edge, corner, and face-sharing NiNd4Al2Ni6 cuboctahedra. Al(1) is bonded in a 8-coordinate geometry to four equivalent Nd(1), four equivalent Ni(1), and four equivalent Ni(2) atoms.
NdNi4Al crystallizes in the orthorhombic Cmmm space group. Nd(1) is bonded in a 18-coordinate geometry to six equivalent Ni(1), eight equivalent Ni(2), and four equivalent Al(1) atoms. There are two shorter (2.80 Å) and four longer (2.91 Å) Nd(1)-Ni(1) bond lengths. All Nd(1)-Ni(2) bond lengths are 3.18 Å. All Nd(1)-Al(1) bond lengths are 3.23 Å. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 9-coordinate geometry to three equivalent Nd(1), four equivalent Ni(2), and two equivalent Al(1) atoms. All Ni(1)-Ni(2) bond lengths are 2.47 Å. Both Ni(1)-Al(1) bond lengths are 2.46 Å. In the second Ni site, Ni(2) is bonded to four equivalent Nd(1), two equivalent Ni(2), four equivalent Ni(1), and two equivalent Al(1) atoms to form a mixture of distorted edge, corner, and face-sharing NiNd4Al2Ni6 cuboctahedra. Both Ni(2)-Ni(2) bond lengths are 2.54 Å. Both Ni(2)-Al(1) bond lengths are 2.47 Å. Al(1) is bonded in a 8-coordinate geometry to four equivalent Nd(1), four equivalent Ni(1), and four equivalent Ni(2) atoms.