The theoretical calculations some Schiff base derivatives

Schiff bases are compounds that are widely used for different purposes in several areas. A growing body of research focusing on Schiff Bases has existed over the past decades. In this paper, theoretical calculations of some certain Schiff bases previously synthesized were conducted. The calculated Schiff bases are compounds which are Phenylhydrazine Derivate Schiff Bases. It can be noted that hydrogen displays tautomer, depending on nitrogenous in these bases. This situation leads Schiff bases to show varieties in solid and solvent environment. When it comes to determination of form, IR, UV-Vis., NMR, etc. pose some challenges in solid and solvent environments of tautomer forms. Identifying tautomer ratios before the synthesis makes the analysis of the form easier. Additionally, parameters theoretically calculated are expected to shed light on such features as solvatokromizm, optical and electronic. Theoretical calculations of Schiff bases which are a series of substitute Phenylhydrazine Derivate synthesized beforehand were performed through Gaussian 09. Stabilized tautomer forms of these compounds and likely tautomer forms were identifying, by examining in the existence of vacuum and solvent through DFT method B3LYP/6-311g (d,p). In all compounds and likely tautomer forms, sum of electronic and thermal free energies (SETFE), dipole moments, mulliken charges, HOMO-LUMO energies, vibration frequencies (IR), 1H-NMR, 13C-NMR and electronic transition mechanism (UV-Vis spectrums) were calculated by means of vacuum and liquid environment.