DFT: B3LYP/6-311G (d, p) vibrational analysis of bis-(diethyldithiocarbamate)zinc(II) and natural bond orbitals.

Theoretical and experimental bands have been assigned for the Fourier Transform Infrared (FT-IR) and Fourier Transform Raman (FT-Raman) spectra of the bis-(diethydithiocarbamate)Zn(II) complex, [Zn(DDTC)(2)]. The calculations and spectra interpretation have been based on the DFT/B3LYP method, infrared and Raman second derivative spectra as well as band deconvolution analysis. To assign the metal-ligand normal modes the deviation percentage of the geometrical parameters was used. Results confirms a pseudo tetrahedral structure around the Zn(II) cation. The calculated infrared and Raman spectra has an excellent agreement with the experimental spectra. The Natural Bond Orbital analysis (NBO) was carried out as a way to study the Zn(II) hybridization leading to the pseudo tetrahedral geometry of the framework of the [Zn(DDTC)(2)] complex, and to study also which are the donor NBO and the acceptor NBO in meaningful charge transfer through the Second Order Perturbation Theory Analysis of Fox Matrix in NBO basis.