Synthesis and structure characterization of zinc and cadmium dipeptide coordination polymers

Abstract

Two new coordination polymers, Zn(Gly-L-Phe)₂ and Cd(Gly-L-Phe)₂ (Gly-L-Phe = glycyl-L-phenylalanine), have been synthesized by the reaction of Zn(NO₃)₂·6H₂O or Cd(NO₃)₂·6H₂O, NaOH and glycyl-L-phenylalanine. The obtained materials were characterized by infrared spectroscopy, thermal analysis, atomic absorption spectroscopy, while crystal structures were determined from powder X-ray diffraction data. Both products crystallize in the chiral monoclinic C2 space group, having similar unit cell parameters, forming a two-dimensional coordination network, two of which are interpenetrated giving a non-porous structure. Both products show enhanced thermal stability (over 300 °C).