Investigation of spectroscopic and nonlinear optical (NLO) properties of N2 ,N6 -BIS-[4-(aminosulfonyl) phenyl]-pyridine-2,6-dicarboxamide by DFT method

Sulfonamides are organic sulfur compounds containing -SO2NH2 group, and they are compounds with antimicrobial activity and antibacterial activity that prevent the growth of bacteria. The discovery of sulfonamides is an important milestone in human chemotherapeutic history. In 1935, it was found that the dye prontosil was metabolized in vivo to an active compound, sulfanilamide, and this active compound prevented streptococcal infections in mice. In this thesis, the stable structure of N2 ,N6 -bis-[4-(aminosulfonyl)phenyl]-pyridine-2,6-dicarboxamide compound synthesized by Adem Rıza BAYKAN was obtained by DFT method by performing geometry optimization calculation at B3LYP/6-311++G(d,p) level. Since the molecule studied in the literature has no experimental structural parameters, the theoretically calculated bond lengths and bond angles of the compound were compared with the experimental values of similar molecules in the literature. Especially S-O, S-N and N-C bond lengths were calculated as 1.461, 1.695 and 1.382 Ȧ, and it was seen that the calculated results were compatible with the experimental values in the literature. In addition, the spectroscopic properties of the molecule such as FT-IR, 1H-NMR and 13C-NMR were calculated with the same method and basis set. In the obtained FT-IR analysis results, it is seen that the values of 1263 and 1261 cm-1 calculated for the C-N stretching vibration coincide with the values of similar molecular groups in the literature. Finally, the HOMO and LUMO energies of the molecule at the B3LYP/6-311++G(d,p) level were calculated by the DFT method. The obtained HOMO and LUMO energy difference was found to be 4.685 eV. The nonlinear optical properties and molecular potential energy surface map of the studied iicompound were calculated using the same method and basis set. As a result of calculation, the compound was found to have a hyperpolarizability of 2665.2x10-33 esu. This value indicates that the hyperpolarizability of the compound is approximately 7.15 times greater than that of urea. In this thesis study, all calculations were performed with Gaussian 09 (Linux) and Gauss View 5.0 package programs.