Structural and electronic properties of three new Cu(II) complexes with carboxylic ligands: A DFT study

Three copper(II) complexes with carboxylic ligands including: thiophene-2,5-dicarboxylic acid(tdc),2-aminomethylpyridine (ampy) [Cu2(μ-tdc)2(ampy)2] (1), , ethylenediamine (en), N,Ndimethylethylenediamine(nnen), [Cu(tdc)(nnen)2]_H2O (2), N,N′-dimethylethylenediamine (dmen),[Cu(μ-tdc)(H2O)(dmen)] (3), were optimized through DFT/B3LYPL/6-311+G(d,p)/LANL2DZcalculations and their geometry structures compared with the experimental ones. In followings,single point energy, vibrational frequencies, and NBO calculations have been performed. Theoptimized structures of titles complexes show good consistency to selected experimental parameters.The results of NBO calculations have been employed to evaluate the electronic density of differentstructural parts of 1-3 involving the frontier molecular orbitals. It can be suggested which tdc and Cucenter have main role in constructing HOMOs and LUMOs and could affect on electron transferringreaction and related properties of compounds..

Keywords:

Copper complexes , Carboxilic ligand , Thiophene-2 , 5-dicarboxylic acid , 2- aminomethylpyridine , ethylenediamine , Density functional theory