Gd(FeGa2)4 crystallizes in the tetragonal I4/mmm space group. Gd(1) is bonded in a 20-coordinate geometry to eight equivalent Fe(1), four equivalent Ga(2), and eight equivalent Ga(1) atoms. Fe(1) is bonded to two equivalent Gd(1), two equivalent Fe(1), four equivalent Ga(1), and four equivalent Ga(2) atoms to form a mixture of distorted face, corner, and edge-sharing FeGd2Ga8Fe2 cuboctahedra. There are two inequivalent Ga sites. In the first Ga site, Ga(1) is bonded in a 12-coordinate geometry to two equivalent Gd(1), four equivalent Fe(1), two equivalent Ga(1), and four equivalent Ga(2) atoms. In the second Ga site, Ga(2) is bonded in a 10-coordinate geometry to one Gd(1), four equivalent Fe(1), one Ga(2), and four equivalent Ga(1) atoms.
Gd(FeGa2)4 crystallizes in the tetragonal I4/mmm space group. Gd(1) is bonded in a 20-coordinate geometry to eight equivalent Fe(1), four equivalent Ga(2), and eight equivalent Ga(1) atoms. All Gd(1)-Fe(1) bond lengths are 3.32 Å. All Gd(1)-Ga(2) bond lengths are 2.96 Å. All Gd(1)-Ga(1) bond lengths are 3.17 Å. Fe(1) is bonded to two equivalent Gd(1), two equivalent Fe(1), four equivalent Ga(1), and four equivalent Ga(2) atoms to form a mixture of distorted face, corner, and edge-sharing FeGd2Ga8Fe2 cuboctahedra. Both Fe(1)-Fe(1) bond lengths are 2.54 Å. All Fe(1)-Ga(1) bond lengths are 2.53 Å. All Fe(1)-Ga(2) bond lengths are 2.63 Å. There are two inequivalent Ga sites. In the first Ga site, Ga(1) is bonded in a 12-coordinate geometry to two equivalent Gd(1), four equivalent Fe(1), two equivalent Ga(1), and four equivalent Ga(2) atoms. Both Ga(1)-Ga(1) bond lengths are 2.68 Å. There are two shorter (2.75 Å) and two longer (2.80 Å) Ga(1)-Ga(2) bond lengths. In the second Ga site, Ga(2) is bonded in a 10-coordinate geometry to one Gd(1), four equivalent Fe(1), one Ga(2), and four equivalent Ga(1) atoms. The Ga(2)-Ga(2) bond length is 2.76 Å.