Density functional theory (DFT)

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1 - Natural Bond Orbital (NBO) Population Analysis of Iridabenzene (C5H5Ir)(PH3)3
R. Ghiasi E. Ebrahimi Mokaram

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2 - The Stability and Properties of Mn+@ C26-2nBnNn(M= alkaline and earth alkaline metals; n=0, 3) Complexes for Synthesis Application
Reza Ghiasi Hadi Bharifar Simzar Hosseinzade Mohammad Ail Zarinfard Amir Hossein Hakimyoun

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3 - QSAR Study of New Biphenylic Derivatives as CB2 Receptor Ligands by Quantum Chemical Descriptors
Nosrat Madadi Mahani Alireza Mohadesi zarandi Najmeh Mohammadi

A quantitative Structure-Activity Relationship (QSAR) model was applied to the prediction of the activity of new biphenylic derivatives as CB2 biphenyls ligands. The activity biphenylic derivatives were modeled with the descriptors of quantum-chemical calculations with More

A quantitative Structure-Activity Relationship (QSAR) model was applied to the prediction of the activity of new biphenylic derivatives as CB2 biphenyls ligands. The activity biphenylic derivatives were modeled with the descriptors of quantum-chemical calculations with density functional theory (DFT) method at B3LYP/6‒31G level. This study was conducted using the multiple linear regressions (MLR), the partial least square analysis (PLS) and the principal component analysis (PCA) method. Results displayed that the MLR method predicted of activity good enough. The best model, with six descriptors was selected. Also it indicates very good consistency towards data variations for the validation methods. The predicted values of activities are in suitable agreement with the experimental results. The obtained results suggested that the MLR method could be more helpful to predict the biological activity of biphenyls derivatives. It is anticipated to be useful to predict the activity of other compounds in the same groups. Manuscript profile

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4 - Theoretical and experimental tautomerism study of para-Trifluorobenzoylacetone halogen derivatives using DFT and vibrational spectroscopy
Vahidreza Darugar Mohammad Vakili Sayyed Faramarz Tayyari

Analysis of the molecular structure and relative stability for the cis-enol stable forms in trifluorobenzoylacetone and halogenated derivatives was performed by density functional theory (DFT), at level B3LYP / 6-311 ++ G **. In these molecules, there are only two forms More

Analysis of the molecular structure and relative stability for the cis-enol stable forms in trifluorobenzoylacetone and halogenated derivatives was performed by density functional theory (DFT), at level B3LYP / 6-311 ++ G **. In these molecules, there are only two forms of cis-enol that are capable of forming an intra-molecular O-H + O hydrogen bond, which are equilibrium. Our calculations show that the difference between these two forms in para-halotrifluorobenzoylacetone molecules is about 1.49-4.75 kcal/mole, indicating that both forms can exist in the sample. The hydrogen bond strength has also been calculated for the stable enilic forms of this molecule through the AIM software and compared with other parameters related to the hydrogen bond strength, including structural parameters and spectroscopy. According to the results obtained in para-halogenated trifluorobenzoylacetone molecules, the hydrogen bond strength in form-2 is greater than Form-4. Comparison of these results also shows that the chlorine, fluorine and bromine substituents in the para position of phenyl ring have no significant effect on the structure and intramolecular hydrogen bond strength, but can lead to the displacement the bands of the phenyl ring. Manuscript profile

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5 - Molecular Docking and DFT Study On the Interaction Between Quercetin on surface B12N12 Fullerene
Mohammad Taghi Baei

Adsorption and antiradical activity of quercetin molecule on B12N12 fullerene surface have been investigated with the help of density functional theory (DFT) in B3PW91-D and M06-2X-D methods. Adsorption values and topologies analysis showed that this molecule is adsorbe More

Adsorption and antiradical activity of quercetin molecule on B12N12 fullerene surface have been investigated with the help of density functional theory (DFT) in B3PW91-D and M06-2X-D methods. Adsorption values and topologies analysis showed that this molecule is adsorbed to the B12N12 fullerene surface and causes significant changes in the electronic properties of the fullerene. The antioxidant activities of quercetin molecule and B12N12/Que complex have been investigated using M06-2X-D level of theory based on hydrogen atom transfer (HAT), single electron transfer followed by proton transfer (SET-PT) and SPLET method. To better understand the antioxidant properties, the values of bond dissociation enthalpy (BDE), ionization potential (IP), proton dissociation enthalpy (PDE), proton affinity (PA) and electron transfer enthalpy (ETE) of quercetin on the B12N12 fullerene surface in gas, benzene, Ethanol and water have been calculated. The results showed that in gas and solvent phases, the adsorption of quercetin on B12N12 fullerene increased the antioxidant activity of quercetin, the interaction energy and inhibition constant in the molecular docking method also confirm these results. Manuscript profile

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6 - The use of DFT computational method to study the effect of physical factors on the pH range of color change of Azo indicator: Methyl red and Methyl Orange
ahdieh Sadeghpour Farzaneh Zanjanchi

Azo dyes are an important group of indicator that are used as pH sensors and can also be used in the structure of new sensors. In this research, a theoretical study has been conducted on the role of physical factors on the behavior of azo-halochromic dyes. The azo dyes More

Azo dyes are an important group of indicator that are used as pH sensors and can also be used in the structure of new sensors. In this research, a theoretical study has been conducted on the role of physical factors on the behavior of azo-halochromic dyes. The azo dyes studied in this paper are methyl red and methyl orange.The values obtained for the totomeric equilibrium constant show that the azo form of these indicators is more stable than their hydrazone form. Therefore, in this paper, only the relationship between acid-base equiblirum of azo form indicators is investigated. Also, the range of color change of pH indicators and the effect of physical factors on acid-base equiblirum of indicators will be examined. Studies show that increasing the temperature reduces the pH range of the color change of the indicators but the effect of pressure will decrease with increasing pressure, and the type of indicator will not affect this result.Studies also show that increasing polarity of the solvent and the use of isotopes of atoms will decrease the pH range of color change of the indicators. The method used in this research can be help the development of pH-sensitive sensors. Manuscript profile

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7 - Investigating the adsorption and antioxidant properties of Gallic acid on surface the B12N12 fullerene using quantum mechanical DFT and Molecular Docking
Mohammad Taghi Baei khadijeh tavakoli hafshejani

Adsorption and antioxidative activity of Gallic acid (Gal) on the surface of B12N12 fullerene has been investigated by using density functional theory (DFT) within B3PW91-D and M06-2X-D methods. Adsorption values and electronic properties showed that the molecule has ch More

Adsorption and antioxidative activity of Gallic acid (Gal) on the surface of B12N12 fullerene has been investigated by using density functional theory (DFT) within B3PW91-D and M06-2X-D methods. Adsorption values and electronic properties showed that the molecule has chemisorbed to the fullerene surface and induces significant changes in electronic properties of the fullerene. Antioxidative activities of the Gallic acid and Gal/B12N12 complex have been investigated using the M06-2X-D level of theory based on the hydrogen atom transfer (HAT), single electron transfer followed by proton transfer (SET-PT) and sequential proton loss electron transfer (SPLET). For this purpose, the bond dissociation enthalpy (BDE), ionization potential (IP), proton dissociation enthalpy (PDE), proton affinity (PA) and electron transfer enthalpy (ETE) values were calculated in gas, benzene, ethanol, and water phases to better understand the antioxidative properties of the investigated compounds. The results showed that the adsorption of galic acid on B12N12 fullerene would enhance the antioxidative activity of the gallic acid. Manuscript profile

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