The final family of coordination complexes are the eight coordinate f-block metals. Cs 5 [Nd(NCS) 8 ] has a NdN 8 coordination geometry intermediate between cubic and square antiprismatic, whereas Cs 4 [U(NCS) 8 ] has a square antiprismatic UN 8 coordination, Both crystallize with isolated anions in tetragonal space groups, Nd in I4 and U in P4/n.