فهرست مقالات natural charge

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  1 - 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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  2 - A computational investigation on NMR Characterization and electronic properties of some zigzag nanotubes
  M. Anafcheh F. Naderi M. Ezatvar H. Masoomi
  DFT calculations were applied to evaluate the electronic and magnetic properties of zigzag BC2Nnanotubes based on the 13C, 15N, and 11B NMR parameters and natural charge analysis. Weconsidered three types of zigzag nanotubes, ZZ-1, ZZ-2, and ZZ-3 (n, 0) with n = 8, 12, چکیده کامل

  DFT calculations were applied to evaluate the electronic and magnetic properties of zigzag BC2Nnanotubes based on the 13C, 15N, and 11B NMR parameters and natural charge analysis. Weconsidered three types of zigzag nanotubes, ZZ-1, ZZ-2, and ZZ-3 (n, 0) with n = 8, 12, and 14. Theobtained results indicated the divisions of the electrostatic environments around C nuclei into a fewlayers, consistent with the calculated natural charges on C atoms. There was a good correlationbetween the layers of chemical shielding isotropy as well as anisotropy, >iso, and ?>, and the fivelocal structures around carbon atoms. Successive BN units lead to larger 15N >iso values incomparison with the individual BN units in the ZZ-2(n, 0) and ZZ-3(n, 0)). Slight differences in thevalues of 11B >iso clarified diminutive diversity in the electron densities of boron nuclei, while ?>values indicated the more apparent range of changes. پرونده مقاله
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  3 - Theoretical investigations on molecular structure, NBO, HOMO-LUMO and MEP analysis of two crystal structures of N-(2-benzoyl-phenyl) oxalyl: A DFT study
  Masoome Sheikhi Ebrahim Balali Hadi Lari
  The N-(2-benzoyl-phenyl) oxalyl derivatives are important models for studying of three-centered intramolecular hydrogen bonding in organic molecules. The quantum theoretical calculations for two crystal structures of N-(2-benzoyl-phenyl) oxalyl (compounds I and II) were چکیده کامل

  The N-(2-benzoyl-phenyl) oxalyl derivatives are important models for studying of three-centered intramolecular hydrogen bonding in organic molecules. The quantum theoretical calculations for two crystal structures of N-(2-benzoyl-phenyl) oxalyl (compounds I and II) were performed by Density Functional Theory (B3LYP method and 6-311+G* basis set). From the optimized structures, geometric parameters were obtained and experimental measurements were compared with the calculated data. The NMR parameters such as chemical shift isotropic (CSI) and chemical shift anisotropic (CSA), natural charge (NBO), thermodynamic parameters such as relative energy (ΔE), standard enthalpies (ΔH), entropies (ΔS), Gibbs free energy (ΔG) and constant volume molar heat capacity (Cv), frontier molecular orbitals (FMOs), total density of states (DOS), molecular electrostatic potential (MEP) of the two structures were investigated by theoretical calculations. Molecular properties such as Ionisation Potential (I), Electron affinity (A), chemical hardness (η), electronic chemical potential (μ) andelectrophilicity (ω) obtained and three-centered intramolecular hydrogen bonding were investigated by NBO analysis. پرونده مقاله