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Study of Optical and Electrochemical Properties of Solvent-Dependent Natural Dye Extracted from Rivina humilis L

Aliah Hasniah, Iman Ryan N., Sriwidati Sriwidati, Sawitri Asti, Setiawan Andhy, Putri Assa P. D., Kurniawati Fera

Journal of Ecological Engineering

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2023

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Vol. 24, nr 9

312--321

EN

This work aimed to study the natural dye extracted from Indonesian wild plants (Rivina humilis L.) using different solvents. The natural dye was extracted using the maceration method. Three different solvents, namely, aquades, acetone, and ethanol 96%, were used to extract natural dye from Rivina humilis L fruit. The absorbance spectra of the extracted dye were recorded using Ultraviolet-Visible (UV-Vis) spectroscopy. The different spectra of betalain pigment revealed the dye extract’s dependence on the solvent. The functional groups of the extracted dye were analyzed using Fourier transform infrared (FTIR) spectroscopy. The adherence of carbonyl and hydroxyl groups from FTIR spectra indicated that this dye could anchor to a semiconducting material, e.g., TiO2, which was commonly used in dye-sensitized solar cells (DSSC). The electrochemical properties of the extracted pigments were studied through higher occupied molecular orbital (HOMO) and lower unoccupied molecular orbital (LUMO) energy levels. Based on the results, the best performance to construct DSSC was achieved by natural dye adsorption with aquades solvent.

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Theoretical investigations on the structural, spectroscopic, electronic and thermodynamic properties of (3-Oxo-3H-benzo[f]chromen-1yl) methyl N,N-dimethylcarbamodithioate-1ex

Kara M., Evecen M., Özdogan T.

Materials Science Poland

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2017

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Vol. 35, No. 3

560--575

EN

Hartree-Fock and Density Functional Theory (B3LYP, B3PW91) calculations for the ground state of (3-Oxo-3Hbenzo[ f]chromen-1-yl) methyl N,N-dimethylcarbamodithioate have been presented and the calculated structural parameters and energetic properties have been compared with the available X-ray diffraction data. The vibrational frequencies have been calculated using optimized geometry of the molecule. The conformational properties of the molecule have been determined by computing molecular energy properties, in which torsional angle varied from -180° to +180° in steps of 10°. Moreover, natural bond orbital analysis and atomic charge analysis have been performed. Besides, HOMO and LUMO energies have been calculated and their pictures have been presented. Finally, molecular electrostatic potential and thermodynamic properties have been calculated. It is seen that the obtained theoretical results agree well with the available experimental values. In all the calculations, except for optimization and vibrational calculations, B3LYP level of theory with 6-311++G(d,p) basis set has been used.

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Quantum chemical study of organic inhibitors of corrosion and hydrogen absorption an investigation of the mechanism of bainite transformation in experimental 0.2c-1v-2mn steel

Beloglazov G.

Advances in Materials Science

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2012

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Vol. 12, nr 2(32)

5-18

EN

Results of quantum chemical calculations of the molecules of organic inhibitors (Oin) of corrosion and hydrogen absorption by metals (particularly, p-R-C6H4-SO2-NH2 where R= F, Cl, Br, CH3) both in free state and adsorbed on cluster modeling aluminium surface containing 20 atoms of Al are compared to experimental data on efficiencies of protective action (EPA) against corrosion by this metal. Energies of boundary orbitals (HOMO, LUMO) and dipole moments of isolated molecules of Oin as well as changes of atomic charges on Oin atoms when Oin molecule adsorbed have been computed using semi-empiric MNDO quantum chemistry method. It was found that correlation coefficients between EPA and changes of electric charge on N atom [?Q(N)] and O atom [?Q(O)] due to adsorption of Oin on the metal surface are the most significant. At adsorption and eventually the protection action of Oin, the specific role of polar groups (such as hydroxile) and specific role of heteroatoms (such as N, S etc) in the framework of the concepts of molecular orbitals and donor-acceptor interaction between adsorbent and adsorbate.