Nd(FeAs3)4 crystallizes in the cubic Im-3 space group. Nd(1) is bonded to twelve equivalent As(1) atoms to form NdAs12 cuboctahedra that share faces with eight equivalent Fe(1)As6 octahedra. Fe(1) is bonded to six equivalent As(1) atoms to form FeAs6 octahedra that share corners with six equivalent Fe(1)As6 octahedra and faces with two equivalent Nd(1)As12 cuboctahedra. The corner-sharing octahedral tilt angles are 56°. As(1) is bonded in a 5-coordinate geometry to one Nd(1), two equivalent Fe(1), and two equivalent As(1) atoms.
Nd(FeAs3)4 crystallizes in the cubic Im-3 space group. Nd(1) is bonded to twelve equivalent As(1) atoms to form NdAs12 cuboctahedra that share faces with eight equivalent Fe(1)As6 octahedra. All Nd(1)-As(1) bond lengths are 3.13 Å. Fe(1) is bonded to six equivalent As(1) atoms to form FeAs6 octahedra that share corners with six equivalent Fe(1)As6 octahedra and faces with two equivalent Nd(1)As12 cuboctahedra. The corner-sharing octahedral tilt angles are 56°. All Fe(1)-As(1) bond lengths are 2.35 Å. As(1) is bonded in a 5-coordinate geometry to one Nd(1), two equivalent Fe(1), and two equivalent As(1) atoms. There is one shorter (2.57 Å) and one longer (2.60 Å) As(1)-As(1) bond length.