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Abstract
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A 2D coordination polymer of Cu(II) was synthesized by the reaction of CuCl2$2H2O withL-alanine and
characterized by elemental analysis, spectroscopic methods and single crystal X-ray studies. X-ray
analysis indicated that the compound is a 2D coordination polymer which the carboxylate group of
amino acid ligands acts as bridging ligand between Cu(II) ions. The crystal structure of compound is
stabilized by intermolecular hydrogen bond interactions. Magnetic susceptibility data of powdered
sample between 2 and 300 K were interpreted in terms of a 2D-spin model, with weak antiferromagnetic
exchange-coupling throughsyn-anticarboxylate bridges, with coupling constantJ¼0.2 cm
1
between
nearest-neighbor Cu(II) ions. The results are compared with those obtained from similar studies in other
copper amino acid complexes. DFT studies showed that overlap of magnetic dx
2y
2 orbitals of the
neighboring Cu(II) ions and the molecular orbitals of bridging carboxylate groups is negligible what
makes only weak antiferromagnetic interaction between them. Thermal gravimetric analysis (TGA)
indicated that the compound is stable up to 240
C and it converts to CuO at about 800
C. Cyclic voltammetry studies showed a quasi-reversible redox and an irreversible peaks which can be attributed to
Cu(I)/Cu(II) and Cu(II)/Cu(III) couples, respectively
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