AcNd3 is alpha La-derived structured and crystallizes in the tetragonal I4/mmm space group. Ac(1) is bonded to four equivalent Nd(2) and eight equivalent Nd(1) atoms to form AcNd12 cuboctahedra that share corners with four equivalent Ac(1)Nd12 cuboctahedra, corners with eight equivalent Nd(2)Ac4Nd8 cuboctahedra, edges with eight equivalent Ac(1)Nd12 cuboctahedra, edges with sixteen equivalent Nd(1)Ac4Nd8 cuboctahedra, faces with four equivalent Ac(1)Nd12 cuboctahedra, faces with six equivalent Nd(2)Ac4Nd8 cuboctahedra, and faces with eight equivalent Nd(1)Ac4Nd8 cuboctahedra. There are two inequivalent Nd sites. In the first Nd site, Nd(1) is bonded to four equivalent Ac(1), four equivalent Nd(1), and four equivalent Nd(2) atoms to form NdAc4Nd8 cuboctahedra that share corners with twelve equivalent Nd(1)Ac4Nd8 cuboctahedra, edges with eight equivalent Ac(1)Nd12 cuboctahedra, edges with eight equivalent Nd(1)Ac4Nd8 cuboctahedra, edges with eight equivalent Nd(2)Ac4Nd8 cuboctahedra, faces with four equivalent Ac(1)Nd12 cuboctahedra, faces with four equivalent Nd(2)Ac4Nd8 cuboctahedra, and faces with ten equivalent Nd(1)Ac4Nd8 cuboctahedra. In the second Nd site, Nd(2) is bonded to four equivalent Ac(1) and eight equivalent Nd(1) atoms to form NdAc4Nd8 cuboctahedra that share corners with four equivalent Nd(2)Ac4Nd8 cuboctahedra, corners with eight equivalent Ac(1)Nd12 cuboctahedra, edges with eight equivalent Nd(2)Ac4Nd8 cuboctahedra, edges with sixteen equivalent Nd(1)Ac4Nd8 cuboctahedra, faces with four equivalent Nd(2)Ac4Nd8 cuboctahedra, faces with six equivalent Ac(1)Nd12 cuboctahedra, and faces with eight equivalent Nd(1)Ac4Nd8 cuboctahedra.
AcNd3 is alpha La-derived structured and crystallizes in the tetragonal I4/mmm space group. Ac(1) is bonded to four equivalent Nd(2) and eight equivalent Nd(1) atoms to form AcNd12 cuboctahedra that share corners with four equivalent Ac(1)Nd12 cuboctahedra, corners with eight equivalent Nd(2)Ac4Nd8 cuboctahedra, edges with eight equivalent Ac(1)Nd12 cuboctahedra, edges with sixteen equivalent Nd(1)Ac4Nd8 cuboctahedra, faces with four equivalent Ac(1)Nd12 cuboctahedra, faces with six equivalent Nd(2)Ac4Nd8 cuboctahedra, and faces with eight equivalent Nd(1)Ac4Nd8 cuboctahedra. All Ac(1)-Nd(2) bond lengths are 3.78 Å. All Ac(1)-Nd(1) bond lengths are 3.77 Å. There are two inequivalent Nd sites. In the first Nd site, Nd(1) is bonded to four equivalent Ac(1), four equivalent Nd(1), and four equivalent Nd(2) atoms to form NdAc4Nd8 cuboctahedra that share corners with twelve equivalent Nd(1)Ac4Nd8 cuboctahedra, edges with eight equivalent Ac(1)Nd12 cuboctahedra, edges with eight equivalent Nd(1)Ac4Nd8 cuboctahedra, edges with eight equivalent Nd(2)Ac4Nd8 cuboctahedra, faces with four equivalent Ac(1)Nd12 cuboctahedra, faces with four equivalent Nd(2)Ac4Nd8 cuboctahedra, and faces with ten equivalent Nd(1)Ac4Nd8 cuboctahedra. All Nd(1)-Nd(1) bond lengths are 3.78 Å. All Nd(1)-Nd(2) bond lengths are 3.77 Å. In the second Nd site, Nd(2) is bonded to four equivalent Ac(1) and eight equivalent Nd(1) atoms to form NdAc4Nd8 cuboctahedra that share corners with four equivalent Nd(2)Ac4Nd8 cuboctahedra, corners with eight equivalent Ac(1)Nd12 cuboctahedra, edges with eight equivalent Nd(2)Ac4Nd8 cuboctahedra, edges with sixteen equivalent Nd(1)Ac4Nd8 cuboctahedra, faces with four equivalent Nd(2)Ac4Nd8 cuboctahedra, faces with six equivalent Ac(1)Nd12 cuboctahedra, and faces with eight equivalent Nd(1)Ac4Nd8 cuboctahedra.