Calculation of 2- (2- (3-bromophenyl) hydrazone) -5,5-dimethylcyclohexane-1,3-dione bis (thiosemicarbazone) (L) ligand and Ni(II) complex in inhibitory activity on the copper surface by quantum chemical methods

Thiosemicarbazones and metal complexes are widely used compounds due to their important functional groups in their structures.The fact that they are widely used in medicine has increased the interest in these compounds. Since these compounds have electron donor atoms, they act as ligands and show anticancer, antivirus and antibacterial properties. In this study, the compatibility of experimental and theoretical results of the synthesis and characterization of 2-(2-(3-Bromophenyl)hydrazone)-5,5-Bis(thiosemicarbazone) Ligand (L) and Ni(II) complex was investigated. In the theoretical study, calculations were made using the 6-311G(d,p) basis set together with the DFT/B3LYP method in the Gaussian 09W package program. In this study, molecular electrostatic potential map (MEP), energy levels of molecular orbitals (HOMO-LUMO) and inhibitory activity on the copper surface were calculated by quantum chemical methods for ligand (L) and its Ni(II) complex. The spectroscopic (1H-NMR, 13C-N MR, FT-IR and UV-Vis) results of these compounds were investigated theoretically and compared with the experimental results. These results were found to be compatible. The energy difference (ΔE) between HOMO-LUMO was calculated by finding the energies of the highest occupied molecular orbital (HOMO) and the lowest occupied molecular orbital (LUMO). For ligand (L) and complex, HOMO energy was -5.7893 eV and -3.9811 eV, LUMO energy was -2.9873 eV and -3.3756 eV, and band energy (ΔE) was 0.60550 eV and 2.9873 eV, respectively. Inhibitory activity of ligand (L) and Ni(II) complex on Cu(I) and Cu(II) surfaces was investigated. The fraction of transferred electrons (∆N) was found to be 0.6643 eV and 4.2970 eV on the Cu(I) surface, respectively, for the ligand and the complex, and 1.3304 eV and 7.5838 eV on the Cu(II) surface, respectively. According to these results, the inhibitory activity of ligand (L) and Ni(II) complex on the Cu(II) surface is higher than that of Cu(I). In addition, the inhibitory activity on the Cu(II) surface is higher in the Ni(II) complex than in the ligand (L).