Corrigendum to: Oxidation of Aromatic Alkynes with Nitrate Radicals (NO3•): An Experimental and Computational Study on a Synthetically Highly Versatile Radical

Addition of electro- and photochemically generated nitrate radicals, NO3•, to the C≡C triple bond of aromatic alkynes 9a–9h leads to formation of 1,2-diketones 10a–10h. Surprisingly, benzophenones 11a–11h are obtained as by-products, which formally result from loss of a carbon atom. Density functional studies performed with the BHandHLYP method in combination with various basis sets revealed that 1,2-diketones result from 5-endo cyclization of the initially formed vinyl radical and loss of NO•. The key step to benzophenone formation is a γ-cleavage at the stage of the vinyl radical with release of NO2•, followed by Wolff rearrangement of the resulting α-oxo carbene.

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Synthesis, X-Ray Crystallography, Thermal Analysis, and DFT Studies of Ni(II) Complex with 1-Vinylimidazole Ligand

Journal of Crystallography ◽

10.1155/2014/856498 ◽

2014 ◽

Vol 2014 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Fatih Şen ◽

Ramazan Şahin ◽

Muharrem Dinçer ◽

Ömer Andaç ◽

Murat Taş

Keyword(s):

Density Functional ◽

Computational Study ◽

Basis Sets ◽

Mulliken Charge ◽

Monoclinic Space Group ◽

X Ray Diffraction ◽

Dft Methods ◽

X Ray ◽

X Ray Crystallography ◽

The Density Functional Theory

The paper presents a combined experimental and computational study of hexa(1-vinylimidazole)Ni(II) perchlorate complex. The complex was prepared in the laboratory and crystallized in the monoclinic space group P21/n with a=8.442(5), b=13.686(8), c=16.041(9) Å, α=γ=90, β=96.638(5), and Z=1. The complex has been characterized structurally (by single-crystal X-Ray diffraction) and its molecular structure in the ground state has been calculated using the density functional theory (DFT) methods with 6-31G(d) and LanL2DZ basis sets. Thermal behaviour and stability of the complex were studied by TGA/DTA analyses. Besides, the nonlinear optical effects (NLO), molecular electrostatic potential (MEP), frontier molecular orbitals (FMO), and the Mulliken charge distribution were investigated theoretically.

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Computational mechanistic study of the unimolecular dissociation of ethyl hydroperoxide and its bimolecular reactions with atmospheric species

Scientific Reports ◽

10.1038/s41598-020-71881-3 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Mansour H. Almatarneh ◽

Asmaa Alnajajrah ◽

Mohammednoor Altarawneh ◽

Yuming Zhao ◽

Mohammad A. Halim

Keyword(s):

Activation Energy ◽

Density Functional ◽

Computational Study ◽

Basis Sets ◽

Mechanistic Study ◽

Intrinsic Reaction Coordinate ◽

Unimolecular Dissociation ◽

Phase Reaction ◽

Atmospheric Species ◽

Solvation Models

Abstract A detailed computational study of the atmospheric reaction of the simplest Criegee intermediate CH2OO with methane has been performed using the density functional theory (DFT) method and high-level calculations. Solvation models were utilized to address the effect of water molecules on prominent reaction steps and their associated energies. The structures of all proposed mechanisms were optimized using B3LYP functional with several basis sets: 6-31G(d), 6-31G (2df,p), 6-311++G(3df,3pd) and at M06-2X/6-31G(d) and APFD/6-31G(d) levels of theory. Furthermore, all structures were optimized at the B3LYP/6-311++G(3df,3pd) level of theory. The intrinsic reaction coordinate (IRC) analysis was performed for characterizing the transition states on the potential energy surfaces. Fifteen different mechanistic pathways were studied for the reaction of Criegee intermediate with methane. Both thermodynamic functions (ΔH and ΔG), and activation parameters (activation energies Ea, enthalpies of activation ΔHǂ, and Gibbs energies of activation ΔGǂ) were calculated for all pathways investigated. The individual mechanisms for pathways A1, A2, B1, and B2, comprise two key steps: (i) the formation of ethyl hydroperoxide (EHP) accompanying with the hydrogen transfer from the alkanes to the terminal oxygen atom of CIs, and (ii) a following unimolecular dissociation of EHP. Pathways from C1 → H1 involve the bimolecular reaction of EHP with different atmospheric species. The photochemical reaction of methane with EHP (pathway E1) was found to be the most plausible reaction mechanism, exhibiting an overall activation energy of 7 kJ mol−1, which was estimated in vacuum at the B3LYP/6-311++G(3df,3pd) level of theory. All of the reactions were found to be strongly exothermic, expect the case of the sulfur dioxide-involved pathway that is predicted to be endothermic. The solvent effect plays an important role in the reaction of EHP with ammonia (pathway F1). Compared with the gas phase reaction, the overall activation energy for the solution phase reaction is decreased by 162 and 140 kJ mol−1 according to calculations done with the SMD and PCM solvation models, respectively.

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Computational Study of the Decomposition of Cyclotetramethylenetetranitramine under Impact, Friction, and Electric Fields

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1096.407 ◽

2015 ◽

Vol 1096 ◽

pp. 407-412

Author(s):

Hui Hu ◽

Miao Miao Li ◽

Bao Shan Wang

Keyword(s):

Electric Fields ◽

Energetic Materials ◽

Density Functional ◽

Computational Study ◽

Minimum Energy ◽

High Energy ◽

High Energy Density ◽

Basis Sets ◽

Gas Phases ◽

The Impact

Organic CHNO-containing high energy density materials have been widely used for storing large amounts of the chemical energies which can be rapidly transformed into heat upon various external perturbations during detonation. The sensitivity of the energetic materials is subjected to considerable concern for safety and maintenance. Periodic density functional theory with the all-electron basis sets were employed in this work to unravel the impact, friction, and electric-fields induced decomposition of HMX. The minimum energy paths for the N−NO2homolysis reactions of HMX in the bulk and gas phases were obtained. The surface-enhanced effect on the decomposition of HMX were calculated for both (010) and (100) surfaces. A general theoretical scheme has been proposed to assess the intrinsic mechanic and electrostatic sensitivities of the pure energetic materials.

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New Chalcone Derivative: Synthesis, Characterization, Computational Studies and Antioxidant Activity

Letters in Organic Chemistry ◽

10.2174/1570178616666181130163115 ◽

2019 ◽

Vol 17 (1) ◽

pp. 46-53

Author(s):

Reşat Ustabaş ◽

Nevin Süleymanoğlu ◽

Namık Özdemir ◽

Nuran Kahriman ◽

Ersan Bektaş ◽

...

Keyword(s):

Antioxidant Activity ◽

Density Functional ◽

Computational Study ◽

Dft Method ◽

Basis Set ◽

Basis Sets ◽

Isomeric Form ◽

Compound I ◽

Chalcone Derivative ◽

Reducing Ability

A new chalcone derivative, called as 1-(4-(benzylideneamino)phenyl)-3-(furan-2-yl)prop-2- en-1-one (I), was synthezised and characterized by spectral methods (infrared (IR) and proton and carbon- 13 nuclear magnetic resonance (1H- and 13C-NMR) spectroscopy). A computational study was performed by the density functional theory (DFT) method. Spectral data of compound I optimized by using 6-311G(d,p) and 6-311++G(d,p) basis sets were obtained by 6-311++G(d,p) basis set. The E-Z isomerism for newly synthesized chalcone derivative was investigated by considering four isomeric form, E/E, E/Z, Z/E and Z/Z. The results show that, as assumed and thus named, the chalcone derivative is in the E/E form. In addition, quantum chemical parameters were calculated by using DFT method with 6-311++G(d,p) basis set. Antioxidant activity of compound I was determined by the ferric reducing ability of plasma (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay methods. Compound I has low antioxidant activity.

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Computational Study of D-glucose and its Differential Cognitive Effects on Well-being and Quality of Life

Scientific Inquiry and Review ◽

10.32350/sir/2020/43/1143 ◽

2020 ◽

Vol 4 (3) ◽

pp. 27-37

Author(s):

Sohail Nadeem ◽

Ayesha Mohyuddin ◽

Mohsin Javed ◽

Abdul Hafeez ◽

Tayyaba Jamil ◽

...

Keyword(s):

Density Functional ◽

Computational Study ◽

Well Being ◽

Basis Sets ◽

Functional Theory ◽

Nmr Spectrum ◽

Basic Set ◽

The Density Functional Theory ◽

Ir And Raman

GAMESS computational chemistry package is a freeware available on the web. It has been successfully applied for the structure elucidation of the commonly available D-glucose. In the current research, IR and Raman spectra of D-glucose were theoretically calculated by utilizing the density functional theory (DFT), combined with B3LYP/3-21G basic set. IR and Raman activities were estimated through the GAMESS computational package. Moreover, the NMR spectrum was also obtained through the Gaussian 09 package. Theoretically calculated and experimentally calculated results were compared using the B3LYP/3-21G level of theory. The results of both calculations were nearly the same. The optimization of structure with the various levels of theory and Basis sets was studied and the best results were obtained using B3LYP/3-21G, and these results agreed considerably with the experimental results. The current computational analysis may be useful to predict complex carbohydrate precursors and other carbohydrate molecules.

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A Computational Study on Structural and Electronic Properties of 1-(4-Chlorophenyl)-2-{[5-(4-Chlorophenyl)-1,2,3-Oxadiazol-2-Yl]Sulfanyl}Ethanone

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.892.1 ◽

2019 ◽

Vol 892 ◽

pp. 1-7

Author(s):

Pek Lan Toh ◽

Montha Meepripruk ◽

Rosfayanti Rasmidi

Keyword(s):

Density Functional ◽

Computational Study ◽

Molecular System ◽

Population Analysis ◽

Atomic Charge ◽

Dft Method ◽

Basis Sets ◽

Hydrogen Atoms ◽

Mulliken Population ◽

Total Energies

In this paper, a first principle Density Functional Theory (DFT) method was conducted to study the geometric and electronic structures of 1-(4-chlorophenyl)-2-{[5-(4-chlorophenyl) -1,3,4-oxadiazol-2-yl] sulfanyl} ethanone, C16H10Cl2N2O2S. Using B3LYP level of theory with four basis sets of 6-31G**, 6-31++G**, 6-311G**, and 6-311++G**, the equilibrium structure of the title molecule was used to determine the total energies, Frontier molecular orbital’s energies, Mulliken atomic charges, and others. The computed findings present that four total energies obtained are close to each other, with the corresponding values of-59716.06 eV, -59709.42 eV, -59708.56 eV, and-59716.51 eV, respectively for B3LYP/6-31G**, B3LYP/6-31++G**, B3LYP/6-311G**, and B3LYP/6-311++G** methods. The calculated HOMO-LUMO energy gaps were predicted in the range of 4.001 eV - 4.089 eV. In this study, the atomic charge values of molecular system were also determined using Mulliken Population Analysis (MPA) approach. For DFT/B3LYP/6-311G** level of calculation, the computed results show that the atom of C8 accommodates the highest negative charge in the title molecular system. All the oxygen, nitrogen, and chloride atoms are having negative charges, whereas all the hydrogen atoms are having positive charges. In addition, the dipole moment value was also determined to be 1.4758 Debye by employing DFT/B3LYP/6-311G** level of theory.

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Computational Study on the Adsorption of H2SiCl2 by Pristine, Al-, and Ga-Doped Boron Nitride Nanosheets: A DFT Study

10.21203/rs.3.rs-220227/v1 ◽

2021 ◽

Author(s):

Mohsen Doust Mohammadi ◽

hewa y abdullah

Keyword(s):

Electronic Structure ◽

Boron Nitride ◽

Intermolecular Interactions ◽

Density Functional ◽

Computational Study ◽

Basis Sets ◽

Dopant Atom ◽

Total Density ◽

Boron Nitride Nanosheets ◽

Gas Molecule

Abstract The density functional techniques (DFT) were put into practice to study the nature of the intermolecular interactions between Dichlorosilane (H2SiCl2) gas molecule with single-walled pristine, Al and Ga-doped boron nitride nanosheets (BNNS, BNAlNS, and BNGaNS, respectively). For performing optimization process, various functionals including PBE0, M06-2X, ωB97XD, and B3LYP-D3 were applied on both of the isolated and complex structures. All of the functionals were used together with split-valence triple-zeta basis sets with d-type Cartesian-Gaussian polarization functions (6-311G(d)). To consider the electronic structure, total density of state (DOS) analysis were employed. Natural bond orbital (NBO), quantum theory of atoms in molecules (QTAIM), and non-covalent interaction (NCI) analyses were also taken on board to discover the nature of intermolecular interactions between gas and nanosheets. The results of electronic structure calculations as well as population analyses has been carefully tabulated and partially depicted. The HOMO-LUMO energy gaps (HLG) were dramatically changed when the dopant atom added to the BNNS. It means the impurity can improve the sensivity and reactivity of the pristine nanosheet; therefore, by absorbing the H2SiCl2 onto the surface of the titled nanosheets, a salient signal can produce in a typical electronic circuit. Among all of the absorbents, BNGaNT shows the most favorable material to design a nanosensor for the studied gas molecule.

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Proper Gaussian Basis Sets for Density Functional Studies of Water Dimers and Trimers

The Journal of Physical Chemistry B ◽

10.1021/jp055443+ ◽

2005 ◽

Vol 109 (46) ◽

pp. 21471-21475 ◽

Cited By ~ 21

Author(s):

Gábor I. Csonka ◽

Adrienn Ruzsinszky ◽

John P. Perdew

Keyword(s):

Density Functional ◽

Basis Sets ◽

Gaussian Basis Sets ◽

Functional Studies ◽

Water Dimers

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Experimental and Theoretical (ab initio and DFT) Analysis of UV-Vis Spectra, Thermodynamic Functions and Non-linear Optical Properties of 2-Chloro-3,4-Dimethoxybenzaldehyde

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v8i2.1519 ◽

2015 ◽

Vol 8 (2) ◽

pp. 2122-2134

Author(s):

Sarvendra Kumar ◽

Rajesh Kumar ◽

Jayant Teotia ◽

M. K. Yadav

Keyword(s):

Thermodynamic Functions ◽

Title Compound ◽

Density Functional ◽

Structural Characteristics ◽

Basis Sets ◽

Ultraviolet Absorption Spectrum ◽

Non Linear ◽

Different Temperatures ◽

Linear Optical Properties ◽

Linear Optical

In the present work, UV- Visible spectra of 2-Chloro-3,4-Dimethoxybenzaldehyde (2,3,4-CDMB) compoundÂ have been carried out experimentally and theoretically. The ultraviolet absorption spectrum of title compound in three solvents (Acetone, Diethyl Ether, CCl4) of different polarity were examined in the range of 200â€“500 nm. The structure of the molecule was optimized and the structural characteristics were determined by HF and DFT (B3LYP) methods with 6-31+G(d,p) and 6-311++G(d,p) as basis sets. The excitation energy, wavelength corresponds to absorption maxima () and oscillator strength (f) are calculated by Time-Dependent Density Functional Theory (TD-DFT) using B3LYP/6-31+G(d,p) and B3LYP/6-311++G(d,p) as basis sets. The electric dipole moment (Î¼), polarizability (Î±) and the first hyperpolarizability (Î² ) have been computed to evaluate the non-linear optical (NLO) response of the investigated compound by HF and DFT (B3LYP) with already mentioned basis sets. Thermodynamic functions of the title compound at different temperatures were also calculated.

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