Vitamin C is an important human micronutrient. It has many vital biological functions in human health. In this research paper, the molecule of vitamin C was optimized and energy band gaps were determined using DFT and HF methods. In computational quantum theory, Density Functional Theory (DFT) and Hartree-Fock (HF) currently play a significant role in physical chemistry spatially. We chose a 6-311+G basis set on the DFT and HF methods to assess our vitamin C molecule. The FT-IR spectra of vitamin C are reported in the current research. The observed vibrational frequencies are assigned and the computational calculations are performed and the corresponding results are displayed. The structure analysis of the present molecule was investigated by NMR (13C NMR & 1H NMR) and UV-Vis spectra. To assess molecular behavior, Mulliken charge distribution, molecular electrostatic potentials (MEP) and Molecular reactivity description were informed to define the activity of the molecule. All calculations were performed using Gaussian 09 packages.

In this study synthesized and characterization of (1E,1'E)-2,2'-thiobis (1-(3-mesityl-3methylcyclobutyl)ethan-1-one) dioxime for both experimental and computational was reported. The solid-state FT-IR spectrum was observed in the range of 4000-400 cm -1 and CDCl3 solvents were used for 1 H and 13 C NMR analysis. The molecular geometry was calculated using the Density Functional Theory (DFT/B3LYP) method in the ground state with the 6-31G(d, p) basis sets. Vibrational assignments and chemical shifts have been measured theoretically and compared to experimental data. B3LYP/6-31G(d,p) applied on our title compound to found different parameters such as the energy of the highest occupied molecular orbital (E HOMO ), the energy of the lowest unoccupied molecular orbital (E LUMO ), energy gap ( ΔE = E LUMO -E HOMO ) and the dipole moment (μ) related to the corrosion efficacy of organic compounds whose molecular geometry and electronic properties are especially studied were calculated. Properties such as hardness (ɳ), softness (σ), electronegativity (χ) values were computed using these measurement results to inhibitor activity. The fraction of transferred electrons (ΔN) was also calculated, which determined the interaction between the iron surface and the organic compounds. Corrosion inhibitor behavior can therefore be predicted without an experimental study. The findings of the calculations show good relation between organic-based corrosion inhibitors and quantum chemical parameters process.

No abstract

The corrosion inhibitor behaviors of the molecules 1H-Pyrrole, Furan, and Thiophene were examined using the computational quantum method. The density functional theory (DFT) was applied to the 6-31G (d, p) basis set, parameters such as the energy of the highest occupied molecular orbital (E HOMO ), the energy of the lowest unoccupied molecular orbital (E LUMO ), the energy difference (ΔE) and the dipole moment (μ) were calculated. These parameters are correlated with the corrosion effects of organic compounds that are mainly investigated in molecular geometry and electronics. Besides, the chemical hardness (ɳ), softness (σ), electronegativity (χ) has been determined. The transmitted electrons fraction (ΔN) has been determined between cupper surface and the 1H-Pyrrol, Furan and the Thiophene molecule. The parameters that have a direct relation with inhibition efficiency are described. The collected data indicate that 1H-Pyrrole inhibitor provides a good inhibition activity which can be used as a good anti-corrosion agent. There is an inverse relationship between the transmitted electrons fraction (ΔN) and electronegativity (χ) of inhibitor. The behavior of the corrosion inhibitor can therefore be predicted without an experimental analysis.