Two new one-dimensional polymeric metal complexes, namely [Zn(NH3)(mu-4aepy)Ni(mu-CN)(CN)3](n) (1) and [Cu(H2O)(mu-4aepy)Pd(mu-CN)(CN)(3)](n) (2) [4aepy = 4-(2-aminoethyl)pyridine], were synthesized and characterized by vibrational (FT-IR and Raman) spectroscopy, single crystal X-ray diffraction, thermal and elemental analyses techniques. The complexes crystallize in the monoclinic system, P2(1/)n space group. The asymmetric units of 1 and 2 contain two M(II) ions [M = Zn(II) and Ni(II) in 1 and Cu(II) and Pd(II) in 2], four cyanide ligands, one 4aepy ligand and one coordinated ligand (ammine in 1 and aqua in 2) in a distorted tetragonal coordination geometry. The crystal structures of the complexes revealed that three cyanide groups are terminal whereas one different cyanide group behaves as bridging ligand. The most important features of the complexes are the presence of obvious M...pi [M(II) = Ni(II) or Pd(II)] interactions. The spectral and thermal analysis results also support the crystal structures of the complexes. (C) 2016 Elsevier Ltd. All rights reserved.