Nd(FeAl2)4 crystallizes in the tetragonal I4/mmm space group. Nd(1) is bonded in a 20-coordinate geometry to eight equivalent Fe(1), four equivalent Al(1), and eight equivalent Al(2) atoms. Fe(1) is bonded to two equivalent Nd(1), two equivalent Fe(1), four equivalent Al(1), and four equivalent Al(2) atoms to form a mixture of distorted corner, face, and edge-sharing FeNd2Al8Fe2 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 10-coordinate geometry to one Nd(1), four equivalent Fe(1), one Al(1), and four equivalent Al(2) atoms. In the second Al site, Al(2) is bonded in a 12-coordinate geometry to two equivalent Nd(1), four equivalent Fe(1), two equivalent Al(2), and four equivalent Al(1) atoms.
Nd(FeAl2)4 crystallizes in the tetragonal I4/mmm space group. Nd(1) is bonded in a 20-coordinate geometry to eight equivalent Fe(1), four equivalent Al(1), and eight equivalent Al(2) atoms. All Nd(1)-Fe(1) bond lengths are 3.35 Å. All Nd(1)-Al(1) bond lengths are 3.01 Å. All Nd(1)-Al(2) bond lengths are 3.20 Å. Fe(1) is bonded to two equivalent Nd(1), two equivalent Fe(1), four equivalent Al(1), and four equivalent Al(2) atoms to form a mixture of distorted corner, face, and edge-sharing FeNd2Al8Fe2 cuboctahedra. Both Fe(1)-Fe(1) bond lengths are 2.52 Å. All Fe(1)-Al(1) bond lengths are 2.66 Å. All Fe(1)-Al(2) bond lengths are 2.55 Å. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 10-coordinate geometry to one Nd(1), four equivalent Fe(1), one Al(1), and four equivalent Al(2) atoms. The Al(1)-Al(1) bond length is 2.78 Å. There are two shorter (2.73 Å) and two longer (2.80 Å) Al(1)-Al(2) bond lengths. In the second Al site, Al(2) is bonded in a 12-coordinate geometry to two equivalent Nd(1), four equivalent Fe(1), two equivalent Al(2), and four equivalent Al(1) atoms. Both Al(2)-Al(2) bond lengths are 2.78 Å.