• فهرست مقالات Electronic Properties

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        1 - Detection of mercaptopurine drug by T4,4,4-graphyne and the effect of applied electric field: A density functional theory study
        Roya Majidi
        In the present work, adsorption of mercaptopurine (MP) drug on T4,4,4-graphyne sheet is examined by using density functional theory to explore the feasibility of T4,4,4-graphyne based sensor. The most stable configuration, charge transfer, adsorption energy, electronic چکیده کامل
        In the present work, adsorption of mercaptopurine (MP) drug on T4,4,4-graphyne sheet is examined by using density functional theory to explore the feasibility of T4,4,4-graphyne based sensor. The most stable configuration, charge transfer, adsorption energy, electronic band structures, and density of states are determined. It is found that weak physical adsorption with small charge transfer from T4,4,4-graphyne to MP drug took place. T4,4,4-graphyne sheet is an intrinsic semiconductor with a direct band gap. The energy band gap of T4,4,4-graphyne sheet is sensitive to the MP adsorption and decreases with any decrease in the concentration of the MP drug. Hence, T4,4,4-graphyne is a good candidate to detect the MP drug and its concentration. The electronic properties of T4,4,4-graphyne sheet with adsorbed MP are remarkably modulated by applying a perpendicular electric field. The results reveal that applying the electric field is a helpful method to improve the sensing performance of T4,4,4-graphyne sheet. پرونده مقاله
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        2 - Quantum Chemical Modeling of 1-(1, 3-Benzothiazol-2-yl)-3-(thiophene-5-carbonyl) thiourea: Molecular structure, NMR, FMO, MEP and NBO analysis based on DFT calculations
        Masoome Sheikhi Siyamak Shahab
        In the present work, the quantum theoretical calculations of the molecular structure of the 1-(1, 3-Benzothiazol-2-yl)-3-(thiophene-5-carbonyl) thiourea has been predicted and are evaluated using Density Functional Theory (DFT) in gas phase. The geometry of the title co چکیده کامل
        In the present work, the quantum theoretical calculations of the molecular structure of the 1-(1, 3-Benzothiazol-2-yl)-3-(thiophene-5-carbonyl) thiourea has been predicted and are evaluated using Density Functional Theory (DFT) in gas phase. The geometry of the title compound was optimized by B3LYP/6-311+G and B3LYP/6-311+G* methods and the experimental geometrical parameters of the title compound such as bond lengths (Å), bond angles (°) and torsion angels (°) were compared with calculated results. The theoretical 1H and 13C NMR chemical shift (GIAO method) values of the title compound are calculated and compared with the experimental results. The computed data are in good agreement with the experimental data. Frontier molecular orbitals (FMOs) such as HOMO orbital, LUMO orbital and HOMO-LUMO energy gap, molecular electrostatic potential (MEP), electronic properties such as ionization potential, electron affinity, global hardness, electronegativity, electronic chemical potential, electrophilicity, chemical softness and NBO analysis of the title compound were investigated and discussed by theoretical calculations. پرونده مقاله
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        3 - Quantum Chemical Modeling of N-(2-benzoylphenyl)oxalamate: Geometry Optimization, NMR, FMO, MEP and NBO Analysis Based on DFT Calculations
        Masoome Sheikhi Siyamak Shahab Ali Ramazani
        In the present work, the quantum theoretical calculations of the molecular structure of the (N-(2-benzoylphenyl) oxalamate has been investigated and are evaluated using Density Functional Theory (DFT). The geometry of the title compound was optimized by B3LYP method wit چکیده کامل
        In the present work, the quantum theoretical calculations of the molecular structure of the (N-(2-benzoylphenyl) oxalamate has been investigated and are evaluated using Density Functional Theory (DFT). The geometry of the title compound was optimized by B3LYP method with 6-311+G(d) basis set. The theoretical 1H and 13C NMR chemical shift (GIAO method) values of the title compound are calculated and compared with the experimental results. The computed data of the chemical shift are in good agreement with the experimental data. Frontier molecular orbitals (FMOs) such as HOMO orbital, LUMO orbital and energy gap between HOMO and LUMO, molecular electrostatic potential (MEP), electronic properties such as ionization potential (I), electron affinity (A), global hardness, global hardness (η), electronegativity (χ), electronic chemical potential (μ), electrophilicity (ω) and chemical softness (S) of the title compounds were investigated discussed by theoretical calculations. The FMO analysis suggests that charge transfer is taking place within the molecule. Also the electronic structure of the title compound was studied by using Natural Bond Orbital (NBO) analysis in order to understand hyper conjugative interactions and charge delocalization. پرونده مقاله
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        4 - Quantum Chemical Modeling of 2-(Cyclohexylamino)-2-oxo-1-(quinolin-4-yl)ethyl 4-Chlorobenzoate: Molecular Structure, Spectroscopic (FT-IR, NMR, UV) Investigations, FMO, MEP and NBO Analysis Based on HF and DFT Calculations
        Mehdi Nouri Angoran Ali Ramazani Masoome Sheikhi
        In the present work, the quantum theoretical calculations of the molecular structure of the compound 2-(Cyclohexylamino)-2-oxo-1-(quinolin-4-yl)ethyl 4-Chlorobenzoate have been predicted using Density Functional Theory (DFT) in the gas phase. The geometry of the title s چکیده کامل
        In the present work, the quantum theoretical calculations of the molecular structure of the compound 2-(Cyclohexylamino)-2-oxo-1-(quinolin-4-yl)ethyl 4-Chlorobenzoate have been predicted using Density Functional Theory (DFT) in the gas phase. The geometry of the title structure was optimized by B3LYP/6-31+G* and HF/6-31+G* levels of theory. The theoretical 1H and 13C NMR chemical shift values of the title structure are calculated and compared with the experimental results. The calculated results are in good agreement with the experimental data. The theoretical vibrational frequencies values are obtained and compared with the experimental data. The electronic spectra of the title structure in the gas phase were carried out by TDB3LYP/6-31+G* and TDHF/6-31+G* levels of theory. Frontier molecular orbitals (FMOs), the molecular electrostatic potential (MEP), natural charges distribution (NBO charges), electronic properties such as ionization potential (I), electron affinity (A), global hardness (η), electronegativity (χ), electronic chemical potential (μ) and electrophilicity (ω), chemical softness (S=1/η), and NBO analysis were investigated and discussed by theoretical calculations. پرونده مقاله
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        5 - Investigations on Optoelectronic Properties of New low Gap Compounds Based on Pyrrole as Solar Cells Materials
        O. Ninis S.M. Bouzzine H. Toufik F. Lamchouri M. Abarkan M. Hamidi M. Bouachrine
        In this paper theoretical study by using DFT method on three conjugated compound based on 2-styryl-5-phenylazo-pyrrole is reported. These dyes contain one carboxy, two carboxy and one sulfonic acid anchoring groups, the aim is to investigate their effects on the electro چکیده کامل
        In this paper theoretical study by using DFT method on three conjugated compound based on 2-styryl-5-phenylazo-pyrrole is reported. These dyes contain one carboxy, two carboxy and one sulfonic acid anchoring groups, the aim is to investigate their effects on the electronic structure. The theoretical knowledge of the HOMO and LUMO energy levels of the components is cannot be ignored in investigating suitable materials for organic solar cells so the HOMO, LUMO and gap energies of the studied compound have been calculated and reported. These properties suggest these materials as good candidates for organic solar cells. پرونده مقاله
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        6 - Investigations of New Low Gap Conjugated Compounds Based on Thiophene-Phenylene as Solar Cells Materials
        Mansour Amine Amina Amine Mohammed Hamidi Si Mohammed Bouzzine Mohammed Bouachrine
        The research in new organic π-conjugated molecules with specific properties has become one of the most interesting topics in fields of materials chemistry. These materials are promising for optoelectronic device technology such as solar cells. On the other hand, the چکیده کامل
        The research in new organic π-conjugated molecules with specific properties has become one of the most interesting topics in fields of materials chemistry. These materials are promising for optoelectronic device technology such as solar cells. On the other hand, the use of low band gap materials is a viable method for better harvesting of the solar spectrum and increasing its efficiency. The control of this parameter of these materials is research issue of ongoing interest. In this work, quantum chemical investigation has been performed to explore the optical and electronic properties of a series of different compounds based on thiophenephenylene. Different electron side groups were introduced to investigate their effects on the electronic structure. The theoretical knowledge of the HOMO and LUMO energy levels of the components is basic in studying organic solar cells so the HOMO, LUMO and Gap energy of the studied compounds have been calculated and reported. These properties suggest these materials as a good candidate for organic solar cells. پرونده مقاله
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        7 - A Combined Experimental and Theoretical Study of Optoelectronic and Structural Properties of a New Copolymer Based on Polyvinylcarbazole (PVK) and Poly (3-hexylthiophene) (PHT)
        Z. El Malki L. Bejjit M. Haddad M. Hamidi M. Bouachrine
        In this paper we report on a combination of experimental and theoretical study of a new copolymer based on carbazole and methylthiophene (Cbz-Mth), in their neutral and oxidized states. We discuss the influence of chain length on conformational and optoelectronic proper چکیده کامل
        In this paper we report on a combination of experimental and theoretical study of a new copolymer based on carbazole and methylthiophene (Cbz-Mth), in their neutral and oxidized states. We discuss the influence of chain length on conformational and optoelectronic properties with the DFT method. Conformational analysis shows that there are no big changes in the structural parameters of neutral oligomers. In the doped form, the oligomer structures become nearly planar and show a quinoidal character. The results obtained for (Cbz-Mth)3 from the neutral state, are close to experimental values. پرونده مقاله
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        8 - Quantum Chemical Investigation of the Photovoltaic Properties of Conjugated Molecules Based Oligothiophene and Carbazole
        N. Belghiti M.N. Bennani Si Mohamed Bouzzine Mohamed Hamidi Mohamed Bouachrine
        The research in the organic π-conjugated molecules and polymers based on thiophenehas become one of the most interesting topics in the field of chemistry physics and materials science. These compounds have become the most promising materials for the optoelectronic de چکیده کامل
        The research in the organic π-conjugated molecules and polymers based on thiophenehas become one of the most interesting topics in the field of chemistry physics and materials science. These compounds have become the most promising materials for the optoelectronic device technology.. The use of low band gap materials is a viable method for better harvesting of the solar spectrum and increasing its efficiency. The control of the band gap of these materials is a research issue of ongoing interest. In this work, a quantum chemical investigation has been performed to explore the optical and electronic properties of a series of different compounds based onthiophene and carbazole. Different electron side groups were introduced to investigate their effects on the electronic structure. The theoretical knowledge of the HOMO and LUMO energy levels of the components is basic in studying organic solar cells so the HOMO, LUMO and Gap energy of the studied compounds have been calculated and reported. These properties suggest these materials as a good candidate for organic solar cells. پرونده مقاله
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        9 - A computational study of N2 adsorption on aromatic metal Mg16M;(M=Be, Mg, and Ca) nanoclusters
        Mahmood Reza Dehghan Sara Ahmadi
        Metal nanoclusters have been considered as a new class of chemical sensors due to their unique electronic structures and the particular physicochemical properties. The interaction of N2 molecule with neutral and ionic magnesium nanoclusters , as well as neutral magnesiu چکیده کامل
        Metal nanoclusters have been considered as a new class of chemical sensors due to their unique electronic structures and the particular physicochemical properties. The interaction of N2 molecule with neutral and ionic magnesium nanoclusters , as well as neutral magnesium nanoclusters with the centrality of beryllium and calcium Mg16M (M=Be, Mg, and Ca) have been investigated using CAM-B3LYP/6-311+G(d) level of theory in the gas phase. The electronic properties of magnesium nanoclusters were significantly affected by the adsorption of N2 molecule. The NBO analysis revealed a charge transfer from the adsorbed N2 molecule to the nanocluster. Based on the adsorption energies and enthalpies, a thermodynamically favorable chemisorption process was predicted for the Mg16Ca—N2 complex. The negative value of the Gibbs free energy of Mg16Ca—N2 confirmed the spontaneous adsorption process. The estimated recovery time for Mg16Ca—N2 complex for 8-MR (0.089 s) and 4-MRs (0.075 s) illustrated a possible desorption process for N2 molecule from the surface of Mg16Ca. Our finding also revealed the Mg16Ca has the ability to use as a sensor for detection and absorption of N2 molecule. پرونده مقاله
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        10 - Exploration of the adsorption of caffein molecule on the TiO2 nanostructures: A density functional theory study
        Amirali Abbasi Jaber Jahanbin Sardroodi
        First principles calculations were performed to study the adsorption behaviors of caffein molecule on the pristine and N-doped TiO2 anatase nanoparticles. Both oxygen and nitrogen in the caffein molecule can react with the TiO2 nanoparticle strongly. Thus, the binding s چکیده کامل
        First principles calculations were performed to study the adsorption behaviors of caffein molecule on the pristine and N-doped TiO2 anatase nanoparticles. Both oxygen and nitrogen in the caffein molecule can react with the TiO2 nanoparticle strongly. Thus, the binding sites were located on the oxygen or nitrogen atom of the caffein, while on the TiO2 nanoparticle the binding site occurs on the fivefold coordinated titanium atoms. By counting van der Waals (vdW) interactions, it was found that the adsorption on the N-doped TiO2 is more favorable in energy than the adsorption on the undoped one, indicating the high sensitivity of N-doped TiO2 nanoparticles towards caffein molecules. It means a dominant effect of nitrogen doping on the adsorption properties of pristine TiO2. The large overlaps in the PDOS spectra of the oxygen and nitrogen atoms of the caffein and titanium atom of TiO2 represent a forming Ti-O and Ti-N bonds between them. The molecular orbital calculation results indicate that the HOMOs are strongly localized on the caffein. Charge analysis based on Mulliken charges reveals a considerable charge transfer from the caffein to the TiO2 nanoparticle. پرونده مقاله
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        11 - Ab initio (first principle) material modeling study on Lio adsorbed by palladium-cobalt (PdCo) nanoparticles
        Mikail Aslan
        PdCo subnanoalloys have been commonly used as a catalytic material in some important chemicalreactions, involving in fisher-tropsch reactions, and oxygen reduction reactions. In terms ofunderstanding the role of catalysis, these smallest bimetallic nanoparticles provide چکیده کامل
        PdCo subnanoalloys have been commonly used as a catalytic material in some important chemicalreactions, involving in fisher-tropsch reactions, and oxygen reduction reactions. In terms ofunderstanding the role of catalysis, these smallest bimetallic nanoparticles provide the simplestprototypes of Pd-Co bimetallic catalysts for different compositions. In this study, the effect ofLixO (x=1,2) on PdCo nanoalloys has been investigated comprehensively employing the densityfunctional theory (DFT) to identify the mechanism of structural, electronic, and energeticproperties of the studied species. Binding energies are calculated for stability analysis, whichis very important for nanoparticles. Results show that lithium oxides are generally adsorbed bycobalt sites on the Pd-Co substrate. This is important for determining active sites of the catalyticmaterial. Furthermore, the structures have low symmetric properties. Hence, this study mightprovide an initial structural evaluation step for future studies related to the possible new catalyticmaterial of Li-air batteries. پرونده مقاله
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        12 - Exploration of the adsorption of caffeine molecule on the TiO2 nanostructures: A density functional theory study
        Amirali Abbasi
        The first principles were calculated to study the adsorption behaviors of caffeine molecules on the pristineand N-doped TiO2 anatase nanoparticles. Both oxygen and nitrogen in the caffeine molecule can reactstrongly with TiO2 nanoparticle. Thus, the binding sites were l چکیده کامل
        The first principles were calculated to study the adsorption behaviors of caffeine molecules on the pristineand N-doped TiO2 anatase nanoparticles. Both oxygen and nitrogen in the caffeine molecule can reactstrongly with TiO2 nanoparticle. Thus, the binding sites were located on the oxygen or nitrogen atom ofthe caffeine, while the binding site of the TiO2 nanoparticle occurs on the fivefold coordinated titaniumatoms. Counting van der Waals (vdW) interactions showed that adsorption on the N-doped TiO2 is morefavorable in energy than the adsorption on the undoped one that indicates the high sensitivity of N-dopedTiO2 nanoparticles towards caffeine molecules. This condition refers to a dominant effect of nitrogendoping on the adsorption properties of pristine TiO2. The existence of large overlaps in the PDOS spectraof the oxygen and nitrogen atoms of the caffeine and titanium atom of TiO2 represent forming Ti-O andTi-N bonds between them. The results of molecular orbital calculation demonstrate that the HOMOsare strongly localized on the caffeine. Charge analysis based on Mulliken charges reveals a considerablecharge transfer from the caffeine to the TiO2 nanoparticle. پرونده مقاله
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        13 - Computational study on geometric and electronic properties of 3.6-carbazole based conjugated polymers
        Mohammed Bouachrine Kenza Hasnaoui Abdellatif Makayssi Mohammed Hamidi
        In this work, we present firstly a study based on the calculation of the local spin densities of radical cations, which is known as a good measure of reactivity for coupling reactions, to obtain a theoretical basis for the one-step formation of poly(3.6-carbazole) and d چکیده کامل
        In this work, we present firstly a study based on the calculation of the local spin densities of radical cations, which is known as a good measure of reactivity for coupling reactions, to obtain a theoretical basis for the one-step formation of poly(3.6-carbazole) and derivatives. Then we detail a DFT theoretical study of the geometric and electronic properties of oligomers based on carbazole and other conjugated monomers. These results will be compared with the experimental ones and with works realized by other authors پرونده مقاله