The CBS values of ΔfHo298.15 and So298.15 Of the phenoxy radicals, formed by abstraction of H atom from the components of surrogate bio-oil
Publication date: Available online 22 October 2019Source: Computational and Theoretical ChemistryAuthor(s): G.A. PoskrebyshevAbstractIn the present work, the standard thermochemical properties of the most thermochemically stable radicals, produced by abstraction of the hydrogen atom from 2,4-dimethylphenol (2,4-xylenol), 2-methoxy-4-methylphenol, 3-methoxy-4-formylphenol (vanillin), are determined using the results of RO/CBS-4M and RO/CBS-QB3 calculations. It is found that the formation of phenoxy radicals is the most thermochemically favorable pathway for the H atom abstraction from the considered compounds.The consistent...
Source: Computational and Theoretical Chemistry - October 23, 2019 Category: Chemistry Source Type: research

DFT Calculations of the Structural, Electronic, Optical and Vibrational Properties of Anhydrous Orthorhombic L-Threonine Crystals
Publication date: Available online 21 October 2019Source: Computational and Theoretical ChemistryAuthor(s): Roniel L. Araújo, Manoel S. Vasconcelos, Carlos A. Barboza, José X. Lima Neto, Eudenilson L. Albuquerque, Umberto L. FulcoAbstractThe structural, electronic, optical, vibrational and thermodynamic properties of the anhydrous orthorhombic L-threonine crystals are investigated by ab initio simulation using a pseudopotential approach within the density functional theory (DFT) method. We have considered both the generalized gradient approximation with dispersion correction (GGA+TS) and the local density app...
Source: Computational and Theoretical Chemistry - October 22, 2019 Category: Chemistry Source Type: research

The Effects of Substituent Position and Orientation on the Structures and Dipole Moments of the Cyanocyclohexanes Using Density Functional Theory Calculations
Publication date: Available online 21 October 2019Source: Computational and Theoretical ChemistryAuthor(s): Kyle D. McNamara, Robert W. ZoellnerAbstractThe effects of position and orientation (axial/equatorial) on the structures and dipole moments of all possible cyano-substituted cyclohexanes were examined using B3LYP/6-311++G**. All optimized molecules exhibited the chair conformation; molecules exhibiting dipole moments ≥6.00 D were examined to determine the effect of substituent position and orientation on the dipole moment. Axial substituents had a greater effect than did equatorial on the dipole moment. For confor...
Source: Computational and Theoretical Chemistry - October 22, 2019 Category: Chemistry Source Type: research

Mechanism of H2 Generation on the Unsaturated Mo and S of Mo-Edge in 2H-MoS2 from Density Functional Theory
Publication date: Available online 19 October 2019Source: Computational and Theoretical ChemistryAuthor(s): Yan-Xia Han, Li-Jie Hou, Qi Zhang, Bo-Wan Wu, Chao Kong, Zhi-Yuan GengAbstractIn this paper, the mechanisms of H2 evolution over the Mo-Edge of 2H-MoS2 with the unsaturated Mo (MoU) and S (SU) were investigated by the density functional theory. The calculations indicated that MoU was a key active site for H2 evolution. In the process of H2 evolution, the SU firstly absorbed H atom by the Volmer reaction, which caused the aggregation of electron on MoU, resulting in the barriers reduction of H transfer and H2 evolutio...
Source: Computational and Theoretical Chemistry - October 20, 2019 Category: Chemistry Source Type: research

Oxygen reduction reaction on TiO2 rutile (1 1 0) surface in the presence of bridging hydroxyl groups
Publication date: 15 November 2019Source: Computational and Theoretical Chemistry, Volume 1168Author(s): Ádám Ganyecz, Pál D. Mezei, Mihály KállayAbstractThe goal of this study is to provide insight into the mechanism of the oxygen reduction reaction on the TiO2 rutile (1 1 0) surface in the presence of bridging hydroxyl groups. Considering the Langmuir–Hinshelwood and Eley–Rideal mechanisms, each possible intermediate was identified using density functional theory and a cluster model along with the energy barriers of the reduction steps and the OO bond breaking. Our resul...
Source: Computational and Theoretical Chemistry - October 14, 2019 Category: Chemistry Source Type: research

How do halogen atoms affect Xe-Mo double bond? A theoretical study of X2XeMoY2 (X = F, Cl, Br; Y = F, Cl, Br)
Publication date: 15 November 2019Source: Computational and Theoretical Chemistry, Volume 1168Author(s): Rui Zhao, Li Sheng, Kunqi GaoAbstractThe X2XeMoY2 (X = F, Cl, Br; Y = F, Cl, Br) compounds were investigated at the B3LYP/Aug-cc-pVTZ level of theory. The calculated molecular structures suggested that the Xe and Mo atoms form a double bond, which supported by the molecular orbital (MO) analysis. Our results showed that in the X2XeMoY2 molecules, the Xe-Mo bond length is shorter when the electronegativity of X atom is stronger and the electronegativity of Y atom is weaker. Interestingly, an unexpectedly short Mo...
Source: Computational and Theoretical Chemistry - October 14, 2019 Category: Chemistry Source Type: research

Editorial Board
Publication date: 1 November 2019Source: Computational and Theoretical Chemistry, Volume 1167Author(s): (Source: Computational and Theoretical Chemistry)
Source: Computational and Theoretical Chemistry - October 13, 2019 Category: Chemistry Source Type: research

A theoretical study of hypothetical silicon analogs of simplest saccharide molecules
Publication date: Available online 9 October 2019Source: Computational and Theoretical ChemistryAuthor(s): Denis Sh. Sabirov, Igor S. ShepelevichAbstractThe silicon-containing saccharide-like molecules have been studied with DFT computational methodology. A principal chemical possibility of the silicon analogs of glyceraldehyde, dihydroxyacetone, β-D-ribopyranose, β-D-deoxyribopyranose, and α-D-glucopyranose) has been shown. The IR spectra of such sila-sugars should contain the bands in the region 2000−2200 cm–1 corresponding to the stretching modes of Si–H bonds. Physicochemical and chemi...
Source: Computational and Theoretical Chemistry - October 11, 2019 Category: Chemistry Source Type: research

Oxygen reduction reaction on TiO2 rutile (110) surface in the presence of bridging hydroxyl groups
Publication date: Available online 4 October 2019Source: Computational and Theoretical ChemistryAuthor(s): Ádám Ganyecz, Pál D. Mezei, Mihály KállayAbstractThe goal of this study is to provide insight into the mechanism of the oxygen reduction reaction on the TiO2 rutile (110) surface in the presence of bridging hydroxyl groups. Considering the Langmuir–Hinshelwood and Eley–Rideal mechanisms, each possible intermediate was identified using density functional theory and a cluster model along with the energy barriers of the reduction steps and the O–O bond breaking. Our re...
Source: Computational and Theoretical Chemistry - October 4, 2019 Category: Chemistry Source Type: research

Multicenter Bonding in s-Block Metals: An Insight from Theory
Publication date: Available online 30 September 2019Source: Computational and Theoretical ChemistryAuthor(s): Amlan Jyoti Kalita, Shahnaz S. Rohman, Chayanika Kashyap, Sabnam S. Ullah, Sohel Reza, Bichitra Borah, Ankur Kanti GuhaAbstractMulticenter bonding, one of the common phenomenon in p-block as well as d-block metals, is a rare phenomenon in s-block metals. Very few examples, if not none, are there in the literature. Herein, we have proposed a 3c-2e bonding scenario involving alkaline earth metals. Different bonding analyses confirm the presence of multicenter 3c-2e bonds in these proposed compounds. All these analyse...
Source: Computational and Theoretical Chemistry - October 1, 2019 Category: Chemistry Source Type: research

Density functional calculations of the adsorption and decomposition of RDX-AP on Al (1 1 1) surface
Publication date: 1 November 2019Source: Computational and Theoretical Chemistry, Volume 1167Author(s): Yubing Liu, Shuhai Zhang, Ruijun Gou, Que Huang, Zhibao Jiang, Minghua Chen, Hongfei GaoAbstractThe adsorption and decomposition mechanisms of RDX-AP on Al (1 1 1) surface (ternary system) were investigated by using the first-principles calculations. After adsorption on Al (1 1 1) surface, RDXAP underwent decomposition accompanying with rupture of NNO2, NN, ClO bonds and formation of new AlN, AlO bonds. Adsorption energy increased with the number of new bonds. There was a strong charge exchange between the RDX/AP...
Source: Computational and Theoretical Chemistry - October 1, 2019 Category: Chemistry Source Type: research

How do Halogen Atoms Affect Xe-Mo Double Bond? A Theoretical Study of X2XeMoY2 (X = F, Cl, Br; Y = F, Cl, Br)
Publication date: Available online 30 September 2019Source: Computational and Theoretical ChemistryAuthor(s): Rui Zhao, Li Sheng, Kunqi GaoAbstractThe X2XeMoY2 (X = F, Cl, Br; Y = F, Cl, Br) compounds were investigated at the B3LYP/Aug-cc-pVTZ level of theory. The calculated molecular structures suggested that the Xe and Mo atoms form a double bond, which supported by the molecular orbital (MO) analysis. Our results showed that in the X2XeMoY2 molecules, the Xe-Mo bond length is shorter when the electronegativity of X atom is stronger and the electronegativity of Y atom is weaker. Interestingly, an unexpectedly short Mo-Y ...
Source: Computational and Theoretical Chemistry - September 30, 2019 Category: Chemistry Source Type: research

Density functional calculations of the adsorption and decomposition of RDX-AP on Al (1 1 1) surface
Publication date: Available online 26 September 2019Source: Computational and Theoretical ChemistryAuthor(s): Yubing Liu, Shuhai Zhang, Ruijun Gou, Que Huang, Zhibao Jiang, Minghua Chen, Hongfei GaoAbstractThe adsorption and decomposition mechanisms of RDX-AP on Al (1 1 1) surface (ternary system) were investigated by using the first-principles calculations. After adsorption on Al (1 1 1) surface, RDXAP underwent decomposition accompanying with rupture of N–NO2, N–N, Cl–O bonds and formation of new Al–N, Al–O bonds. Adsorption energy increased with the number of new bonds. There was a strong c...
Source: Computational and Theoretical Chemistry - September 27, 2019 Category: Chemistry Source Type: research

The high-pressure study of energetic compound DMNA by dispersion-corrected density functional theory calculations
Publication date: Available online 26 September 2019Source: Computational and Theoretical ChemistryAuthor(s): Wen-Peng Wang, Qi-Jun Liu, Fu-Sheng Liu, Zheng-Tang LiuAbstractThe structural and vibrational properties of the typical energetic compound DMNA were studied up to 15 GPa by dispersion-corrected density functional theory (DFT-D) calculations. The calculated crystal structure and vibrational spectra at ambient conditions matched well with the previous experiment and quantum chemical calculations. Further, the lattice parameters, molecular geometry, intermolecular close contacts and Raman spectrum were also examined u...
Source: Computational and Theoretical Chemistry - September 26, 2019 Category: Chemistry Source Type: research

Editorial Board
Publication date: 15 October 2019Source: Computational and Theoretical Chemistry, Volume 1166Author(s): (Source: Computational and Theoretical Chemistry)
Source: Computational and Theoretical Chemistry - September 26, 2019 Category: Chemistry Source Type: research

DFT Studies of Molecular Structures Conformers and Vibrational Characteristics of Sulfanilamide
Publication date: Available online 24 September 2019Source: Computational and Theoretical ChemistryAuthor(s): Gaurav Srivastav, Bhoopendra Yadav, Rohit Kumar Yadav, R.A. YadavAbstractMolecular structures and vibrational parameters for all the four possible conformers of sulfanilamide were studied using Gaussian 09 software and PEDs were calculated using GAR2PED software. MEP and HOMO-LUMO energies were computed and NBO analysis was carried out. Optimized geometries possess Cs symmetry. Out of 51 normal modes, 26 modes are conformer sensitive, out of which 2 modes show frequency variation above 75 cm-1 in going from one con...
Source: Computational and Theoretical Chemistry - September 26, 2019 Category: Chemistry Source Type: research

Quantum chemical study of the complexation process of bis-β-D-glucopyranosyl diazacrown derivative with aspirin and paracetamol molecules
Publication date: Available online 24 September 2019Source: Computational and Theoretical ChemistryAuthor(s): Marta Adamiak, Anna IgnaczakAbstract1,10-N,N’-bis-(β-D-ureidoglucopyranosyl)-4,7,13-trioxa-1,10-diazacyclopentadecane is studied as a potential carrier of aspirin and paracetamol. The host:drug complexes in stoichiometry 1:1 are investigated in aqueous solution using the quantum chemical method B3LYP-GD2/6-31G(d,p) and the polarizable continuum model of solvent. Five new conformers of the host molecule, which are energetically more stable than the one found in the earlier work, [M. Adamiak, S. Porwański...
Source: Computational and Theoretical Chemistry - September 24, 2019 Category: Chemistry Source Type: research

Flutamide drug interaction studies on graphdiyne nanotube – a first-principles study
We report graphdiyne nanotube (Gdn-NT) as a drug carrier for flutamide (FLU) drug to the infected target cell, which is used to cure prostate cancer. In the present research work, first-principles studies were carried out for exploring the charge transfer, band gap, adsorption energy, and average band gap changes; upon interaction of FLU on Gdn-NT. In particular, we studied the solvent effect upon FLU adsorbed Gdn-NT in the report. These important parameters provide the perception of the interaction of the FLU drug onto Gdn-NT, and the favorable interaction sites of FLU on Gdn-NT are also studied. The novel aspects of the ...
Source: Computational and Theoretical Chemistry - September 24, 2019 Category: Chemistry Source Type: research

Theoretical Study of the Internal Rotational Barriers of Fluorine, Chlorine, Bromine, and Iodine-substituted Ethanes
Publication date: Available online 12 September 2019Source: Computational and Theoretical ChemistryAuthor(s): Sílvio Quintino de Aguiar Filho, Adão Marcos Ferreira Costa, Igor Hernandes Santos Ribeiro, Rogério Custodio, Douglas Henrique PereiraAbstractPhysical and chemical characteristics of flexible compounds are extremely dependent of internal rotation barriers. On the other hand, halides of organic compounds are extremely common, and the nature of their rotation barriers are still poorly understood. As a simple example, the experimental height of the internal rotational barrier decreases with the nu...
Source: Computational and Theoretical Chemistry - September 13, 2019 Category: Chemistry Source Type: research

A Coupled Cluster Theory Based on Quantum Electrodynamics: Method for Closed Shells
Publication date: Available online 11 September 2019Source: Computational and Theoretical ChemistryAuthor(s): Sambhu N. DattaAbstractAn electrodynamical coupled cluster (CC) methodology that is based on the standard QED Hamiltonian written using the Dirac-Fock picture of matter fields and Coulomb gauge is discussed here. It employs the combination of a radiative cluster, a pure matter cluster and its pair modification, and relies on the customary CC approach. Averaging over the radiation state is done first, and the cluster operator for radiative effects leads to Lamb, Breit and hyperfine interactions. Relativistic correla...
Source: Computational and Theoretical Chemistry - September 12, 2019 Category: Chemistry Source Type: research

Editorial Board
Publication date: 1 October 2019Source: Computational and Theoretical Chemistry, Volume 1165Author(s): (Source: Computational and Theoretical Chemistry)
Source: Computational and Theoretical Chemistry - September 10, 2019 Category: Chemistry Source Type: research

Quantum Chemical Study on Gas-phase Oligomerization in AlGaN MOCVD Growth
Publication date: Available online 4 September 2019Source: Computational and Theoretical ChemistryAuthor(s): Liu Tang, Ran Zuo, Hong Zhang, Yinmei YuanAbstractThe gas-phase oligomerization reaction path in the growth of AlGaN by MOCVD has been calculated using quantum chemical calculations with density functional theory. The oligomerization of two types amides DMAlNH2 and DMGaNH2 (including heterogeneous oligomerization and homogeneous oligomerization) and subsequent CH4 elimination reactions were investigated at different temperatures. The degree for formation of the various oligomers and the different types of oligomers ...
Source: Computational and Theoretical Chemistry - September 5, 2019 Category: Chemistry Source Type: research

Theoretical Design and Simulations of Hole Transporting Materials Based on 2,2′,7,7′-Tetrakis(N,N-Di-p-Methoxyphenyl-Amine)9,9′-Spirobifluorene for Organic-Inorganic Hybrid Perovskite Solar Cells
Publication date: Available online 3 September 2019Source: Computational and Theoretical ChemistryAuthor(s): Bing Zhang, Yingxue Xu, Jieqin Yang, Yinjie Liao, Lei Tong, Shijie ZhouAbstract2,2′,7,7′-tetrakis(N,N-di-p-methoxyphenyl-amine)9,9′-spirobifluorene represents one of the most effective hole transporting materials in high efficiency perovskite solar cells. Due to the electronic structural diversity of the perovskite material, 20 spirobifluorene derivatives were designed based on the 2,2′,7,7′-tetrakis(N,N-di-p-methoxyphenyl-amine)9,9′-spirobifluorene structural template aiming to a...
Source: Computational and Theoretical Chemistry - September 4, 2019 Category: Chemistry Source Type: research

Composition effect on melting behaviors of Cu-Au-Pt trimetallic nanoalloys
In this study, molecular dynamics simulations were performed on 55-atom icosahedral Cu13AunPt42-n, Au13CunPt42-n and Pt13AunCu42-n (n=1-41) nanoalloys. In order to present the composition effect on the melting behaviors in detail, three different icosahedral compositions corresponding to Cu13Au13Pt29, Au13Cu29Pt13 and Pt13Au29Cu13 were selected from Cu13AunPt42-n, Au13CunPt42-n and Pt13AunCu42-n nanoalloy systems. The temperature dependence of the caloric curve, Lindemann index, heat capacity and root mean square displacement methods was analyzed thoroughly to clarify the simulation results. The simulation results showed t...
Source: Computational and Theoretical Chemistry - September 4, 2019 Category: Chemistry Source Type: research

M(C6H6R)2 (R = BH, Be; M = Cr, Mo, W): Transition-metal sandwich complexes with η7-coordination borepin and beryllepin: A DFT study
Publication date: 1 October 2019Source: Computational and Theoretical Chemistry, Volume 1165Author(s): Yupeng Tang, Yanfei Zhao, Gaofeng Wang, Nan LiAbstractIn this article, the geometrical and electronic structures of a series of borepin and beryllepin transition-metal sandwich complexes M(C6H6R)2 (R = BH, Be; M = Cr, Mo, W) have been systematically investigated at the B3LYP and BP86 levels of theory. Comparing to Cr(C6H6)2, the optimized structures possess the relatively larger binding energies, similar HOMO-LUMO and fundamental gaps. The topology parameters and energy decomposition analyses show the M-C6H6R bond...
Source: Computational and Theoretical Chemistry - September 1, 2019 Category: Chemistry Source Type: research

Design of Active Sites in Zeolite Catalysts using Modern Semiempirical Methods: The Case of Mordenite
Publication date: Available online 30 August 2019Source: Computational and Theoretical ChemistryAuthor(s): Alexander V. Vorontsov, Héctor Valdés, Panagiotis G. SmirniotisAbstractZeolites are widely used for numerous processes for production of a vast number of chemicals, fuels and commercial goods. Preparation of zeolite catalysts that have improved selectivity for the desired products, operate at lower temperature and possess increased stability is therefore of great interest. The key to such improved zeolite catalysts is in the design of active sites and facilitation of mass transfer via optimization of the...
Source: Computational and Theoretical Chemistry - August 31, 2019 Category: Chemistry Source Type: research

Editorial Board
Publication date: 15 September 2019Source: Computational and Theoretical Chemistry, Volume 1164Author(s): (Source: Computational and Theoretical Chemistry)
Source: Computational and Theoretical Chemistry - August 31, 2019 Category: Chemistry Source Type: research

Effect of fluorination of the donor unit on the properties of benzodithiophene-triazole based donor-acceptor systems for polymer solar cells: A computational investigation
Publication date: Available online 28 August 2019Source: Computational and Theoretical ChemistryAuthor(s): Mohd Shavez, Juri Goswami, Aditya N. PandaAbstractThe present computational study is aimed at understanding the effect of introduction of electron-withdrawing fluorine atoms into the donor side of donor-acceptor oligomers for application in solar cells. Starting from reported experimental results, a series of nine benzodithiophene-triazole based oligomers are designed by modifying the benzothiophene unit. Properties such as HOMO-LUMO positions, IPs and EAs, absorptions, optical bandgaps and charge transport properties...
Source: Computational and Theoretical Chemistry - August 29, 2019 Category: Chemistry Source Type: research

The interaction of hyaluronic acid and graphene tuned by functional groups: A density functional study
Publication date: Available online 22 August 2019Source: Computational and Theoretical ChemistryAuthor(s): Qun Wang, Wenqi She, Xiong Lu, Pengfei Li, Yuxi Sun, Xiaodong Liu, Wenhui Pan, Ke DuanAbstractGraphene-hyaluronic acid (HA) composites have desirable physicochemical properties for various biomedical applications. However, pure graphene lacks functional groups for interactions with HA. Thus, surface modification of graphene is frequently required for tailoring their interactions. In this work, interactions of HA and modified graphene were investigated by the density functional theory. Graphene was simulated to be modi...
Source: Computational and Theoretical Chemistry - August 23, 2019 Category: Chemistry Source Type: research

Nanofilter based on functionalized carbon nanostructures for the adsorption of pentachlorophenol molecules
Publication date: Available online 22 August 2019Source: Computational and Theoretical ChemistryAuthor(s): Laura F.O. Vendrame, Tais Zuchetto, Solange Binotto Fagan, Ivana ZanellaAbstractIncreased consumption of industrialized products, medicines, and the mechanization of agribusiness have introduced new contaminants into aquatic systems. Pentachlorophenol (PCP) is a fungicide, insecticide, and bactericide that presents high human toxicity. This paper discusses the use of carbon nanostructures (CNS), such as fullerene, carbon nanotubes and graphene, as possible nanofilter platforms for PCP adsorption. The study shows elect...
Source: Computational and Theoretical Chemistry - August 23, 2019 Category: Chemistry Source Type: research

Interaction properties of benzyl chloride and chlorobenzene on violet phosphorene sheets – a first-principles perception
Publication date: Available online 23 August 2019Source: Computational and Theoretical ChemistryAuthor(s): R. Bhuvaneswari, V. Nagarajan, R. ChandiramouliAbstractIn the present model, we aim to sense the availability of organic compounds, benzyl chloride and chlorobenzene with the help of violet phosphorene (VP). In order to enunciate the utilization of VP as a chief component in detecting the aforementioned volatile organic compounds, ATK-VNL package is applied to scrutinize the geometric and electronic attributes of VP. The electronic properties like band structure, electron density and projected density of states (DOS) ...
Source: Computational and Theoretical Chemistry - August 23, 2019 Category: Chemistry Source Type: research

M(C6H6R)2 (R = BH, Be; M = Cr, Mo, W): Transition-metal sandwich complexes with η7-coordination borepin and beryllepin: A DFT study
Publication date: Available online 23 August 2019Source: Computational and Theoretical ChemistryAuthor(s): Yupeng Tang, Yanfei Zhao, Gaofeng Wang, Nan LiAbstractIn this article, the geometrical and electronic structures of a series of borepin and beryllepin transition-metal sandwich complexes M(C6H6R)2 (R = BH, Be; M = Cr, Mo, W) have been systematically investigated at the B3LYP and BP86 levels of theory. Comparing to Cr(C6H6)2, the optimized structures possess the relatively larger binding energies, similar HOMO-LUMO and fundamental gaps. The topology parameters and energy decomposition analyses show the M-C6H6R bonding ...
Source: Computational and Theoretical Chemistry - August 23, 2019 Category: Chemistry Source Type: research

Hydrogen bonding interaction of N5H with water: A First Principle Calculations
Publication date: Available online 21 August 2019Source: Computational and Theoretical ChemistryAuthor(s): Ravinder Pawar, Venkatesan SubramanianAbstractThe cyclopentazol (N5H) and its anion counterpart (N5–) have been studied extensively over the years and detected in the gas phase as well as in solution recently. In the present investigation, an attempt has been made to understand the interaction with water molecule using first principle calculations. Nature of interactions have been studied using both energy decomposition analysis and atoms in molecule (AIM) theory calculations. Further, the strength of non-covale...
Source: Computational and Theoretical Chemistry - August 22, 2019 Category: Chemistry Source Type: research

The Nature of the Lead-Iodine Bond in PbI2: A Case Study for the Modelling of Lead Halide Perovskites
We report an extensive investigation on the electronic structure and nature of the chemical bond in the PbI2 perovskite precursor, both in gas and solid state, together with a comparison with available experimental data, which allows to effectively calibrate the computational framework, along with gaining basic understanding on the nature of the Pb-I chemical bond. Inclusion of spin orbit coupling and calibrated HF exchange contribution to the DFT hybrid functional are proved essential for an accurate description of the electronic structure of both molecular and solid state PbI2. Such computational framework, calibrated on...
Source: Computational and Theoretical Chemistry - August 19, 2019 Category: Chemistry Source Type: research

Basicity of N-Heterocyclic carbene and its Main-Group Analogues
In this study, the N-heterocyclic carbene (NHC) imidazole-2-ylidene and its analogues species of group13-15 are considered to study their basicity. Proton affinity (PA) and gas phase basicity (GPB) of each species are calculated at the B3LYP/def2-TZVP level of theory. It is found that PA and GPB decrease down a group and along a period. The acidity of the conjugate acid (pKa) of the NHC analogues are computed in solution giving comparable result to the gas phase ones. The binding energies (ΔEbind) of the adduct formation of the carbene analogues with BH3, BF3 and BCl3 are computed at the same level of theory and foll...
Source: Computational and Theoretical Chemistry - August 16, 2019 Category: Chemistry Source Type: research

The structures, stabilities and electronic properties of PdnB (n = 1–10) clusters
Publication date: 15 September 2019Source: Computational and Theoretical Chemistry, Volume 1164Author(s): Jianfeng Wang, Wenshu Hao, Li-Juan Ma, Jianfeng Jia, Hai-Shun WuAbstractRecently experiments proved that Pd catalyst modified with subsurface B atoms had ultra selectivity in selected partial hydrogenation reaction. To make clear the effect of interstitial B atom, the structures, stabilities and electronic properties of PdnB (n = 1–10) clusters have been analyzed by density functional theory. B atom takes residence in octahedral positions of the Pdn, which just is interstitial lattice sites of Pd catalyst. B ...
Source: Computational and Theoretical Chemistry - August 16, 2019 Category: Chemistry Source Type: research

The structures, stabilities and electronic properties of PdnB (n = 1-10) clusters
Publication date: Available online 7 August 2019Source: Computational and Theoretical ChemistryAuthor(s): Jianfeng Wang, Wenshu Hao, Li-Juan Ma, Jianfeng Jia, Hai-Shun WuAbstractRecently experiments proved that Pd catalyst modified with subsurface B atoms had ultra selectivity in selected partial hydrogenation reaction. To make clear the effect of interstitial B atom, the structures, stabilities and electronic properties of PdnB (n = 1-10) clusters have been analyzed by density functional theory. B atom takes residence in octahedral positions of the Pdn, which just is interstitial lattice sites of Pd catalyst. B atom is ea...
Source: Computational and Theoretical Chemistry - August 9, 2019 Category: Chemistry Source Type: research

Water Splitting Activity of Oxygen-Containing Groups in Graphene Oxide Catalyst in Bipolar Membranes
Publication date: Available online 7 August 2019Source: Computational and Theoretical ChemistryAuthor(s): Rodrigo J. Martínez, James FarrellAbstractGraphene oxide (GO) is a very effective catalyst for splitting water into H+ and OH- ions in bipolar membranes. This research investigated the catalytic activity of six oxygenated functional groups in GO for water splitting. Møller-Plesset second order perturbation method (MP2) simulations were performed to calculate activation barriers for proton acceptance and release reactions with and without an applied electric field. The relative catalytic activity for the f...
Source: Computational and Theoretical Chemistry - August 9, 2019 Category: Chemistry Source Type: research

Genoprotection by Complexation: The Case of Phyllanthus orbicularis K Extract
Publication date: Available online 5 August 2019Source: Computational and Theoretical ChemistryAuthor(s): Lázaro A. M. Castanedo, Angel Sánchez Lamar, Cercis Morera Boado, Ania de la Nuez Veulens, Chérif F. MattaAbstractThe aqueous extract of the herb Phyllanthus orbicularis Kunth inhibits the mutagenicity of certain aromatic amines (m-phenilendiamine (m-PDA), 4-aminobiphenyl (4-ABP), and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)). Meanwhile, the phenolic compound 2-6 di-secbutilphenol (DSBP) was isolated from this plant’s extract. Computational evidence is presented to support the p...
Source: Computational and Theoretical Chemistry - August 6, 2019 Category: Chemistry Source Type: research

Quantum-chemical study of oxophosphorus dipyrromethene (PODIPY) fluorophore coordination environment
Publication date: Available online 30 July 2019Source: Computational and Theoretical ChemistryAuthor(s): Artyom Y. Shagurin, Sergey D. Usoltsev, Yuriy S. MarfinAbstractBoron dipyrrin (BODIPY) fluorophores possess a range of excellent spectral characteristics, making their parent structure a useful scaffold for design of optically active molecules. Recently, new oxophosporus dipyrrin (PODIPY) compounds were introduced. They were shown to possess spectroscopic properties similar to those of corresponding BODIPY dyes. However, better solubility in polar solvents makes PODIPY better candidate for in vitro and in vivo fluoresce...
Source: Computational and Theoretical Chemistry - July 31, 2019 Category: Chemistry Source Type: research

Effect of Hubbard parameter and semi-empirical van der Waals correction on benzene adsorption over anatase TiO2 (101) surface
Publication date: Available online 29 July 2019Source: Computational and Theoretical ChemistryAuthor(s): Gustavo Olinto da Silva, João B.L. MartinsAbstractThe present study evaluated the effects of the Hubbard term and the semi-empirical correction of Grimme on adsorption of benzene on the TiO2 anatase surface (101) in relation to the GGA method with the PBE functional. The values of the electron-electron interaction parameter (U) between 0 and 9 eV, Van der Waals corrections of type VDW-D2 and VDW-D3 separately and associated in the same optimization were used. Vibrational data is reported for the adsorption of ben...
Source: Computational and Theoretical Chemistry - July 30, 2019 Category: Chemistry Source Type: research

Dibenzo-p-dioxin. Twisted and puckered excited state molecular geometries
Publication date: Available online 26 July 2019Source: Computational and Theoretical ChemistryAuthor(s): Jens Spanget-LarsenAbstractThe title compound is generally acknowledged to have a planar D2h symmetrical molecular geometry in the ground state S0, and previous theoretical and experimental investigations seem to support the assumption of similar planar geometries in the excited singlet and triplet electronic states, S1 and T1. But a variety of theoretical models predict non-planar equilibrium geometries for these states: In the lowest excited singlet state (S1) a twisted, propeller-like geometry with D2 symmetry is pre...
Source: Computational and Theoretical Chemistry - July 27, 2019 Category: Chemistry Source Type: research

Borane and beryllium derivatives of sulfuric and phosphoric acids: Strong inorganic acids
Publication date: Available online 25 July 2019Source: Computational and Theoretical ChemistryAuthor(s): Younes Valadbeigi, Morteza RouhaniAbstractA new class of strong inorganic acids is designed using substitution of the hydrogen atoms of H2SO4 and H3PO4 by –BX2 and –BeX moieties (X: H, F, Cl, CN, CF3). The acidities of these compounds are assessed by B3LYP/6-311++G(d,p) method in gas phase. These boron and beryllium derivatives are stronger acids than their parents H2SO4 and H3PO4. The acidity of these compounds is attributed to the strong interaction of the oxo group with the Be and B atoms after deprotonat...
Source: Computational and Theoretical Chemistry - July 27, 2019 Category: Chemistry Source Type: research

The values of Δfho298.18(alnomhp), calculated using the cbs correction dependencies, as well as the thermochemistry of the isodesmic/homodesmotic reactions
Publication date: Available online 24 July 2019Source: Computational and Theoretical ChemistryAuthor(s): Gregory A. PoskrebyshevAbstractIn the present work, the tabulated values of ΔfHo298.15(Y=AlnOmHp)TAB are evaluated using the statistical ROCBS-QB3 correction dependence between the tabulated and calculated values of the standard enthalpy of atomization (ΔrHo298.15(ZkOj)atom, Z=H-Cl) of oxides. The good agreement between the values of ΔfHo298.15(Y)TAB and the corrected ROCBS-QB3 values of ΔfHo298.15(Y)CORR is observed in the case of AlO, Al2O2, Al2O3, AlH, AlH2, AlH3 and AlOH.The values of Δ...
Source: Computational and Theoretical Chemistry - July 25, 2019 Category: Chemistry Source Type: research

Toward simple model for the production of lithium phthalocyanine (LiPc) nanoflake through hydrogen transfer processes
Publication date: Available online 23 July 2019Source: Computational and Theoretical ChemistryAuthor(s): Samireh Gohari, Ladan Edjlali, Esmail Vessally, Moosa Es'haghi, Moein GoodarziAbstractThe interesting and unique properties of metal phthalocyanine (MPc) have increased the interest of theoretical and experimental researchers to use the MPc molecules as organic compounds in different reactions. Among different MPc molecules, researchers have had relatively less attention to lithium metal (Li) as lithium phthalocyanine (LiPc). Hereby, we have designed the simple model to produce the LiPc based on the metal free phthalocy...
Source: Computational and Theoretical Chemistry - July 24, 2019 Category: Chemistry Source Type: research

Editorial Board
Publication date: 1 September 2019Source: Computational and Theoretical Chemistry, Volume 1163Author(s): (Source: Computational and Theoretical Chemistry)
Source: Computational and Theoretical Chemistry - July 24, 2019 Category: Chemistry Source Type: research

The low-lying electronic states of HfO2− and HfO2: A symmetry adapted cluster–configuration interaction (SAC-CI) study
Publication date: Available online 22 July 2019Source: Computational and Theoretical ChemistryAuthor(s): Yung-Ching ChouAbstractThe low-lying doublet states of the HfO2− anion and low-lying triplet excited states of the HfO2 molecule were studied using the SAC-CI method. The vertical excitation spectrum of HfO2− was calculated. Four valence-bound states (X2A1, 12B1, 22A1, and 12B2(II)) and one dipole-bound state (2A1(DB)) of HfO2− were found. The vertical electron detachment energies (VDEs) from the ground electronic state of HfO2– to the triplet excited states of HfO2 were obtained. These VDEs were...
Source: Computational and Theoretical Chemistry - July 22, 2019 Category: Chemistry Source Type: research

Is the Iminium Ion Mechanism Viable in the Piperidine-Catalyzed 1,4-Conjugate Addition Reaction of Nitroalkanes to α,β-Unsaturated Ketones?
Publication date: Available online 20 July 2019Source: Computational and Theoretical ChemistryAuthor(s): Virginia C. Rufino, Josefredo R. PliegoAbstractReactions leading to carbon–carbon bond formation, such as the addition of nitroalkanes to α,β-unsaturated ketones, are very important for organic transformations. In the past 15 years, an asymmetric version using amine–thiourea catalysts has been developed. While tertiary amines work via base catalysis, primary and secondary amines are believed to work through iminium catalysis. In this work, we have investigated theoretically the iminium ion catalys...
Source: Computational and Theoretical Chemistry - July 21, 2019 Category: Chemistry Source Type: research

An Ab Initio Study of Double-Electron Oxidized Base Pairs with Diradical Character through Ring-Expansion Modification
Publication date: Available online 20 July 2019Source: Computational and Theoretical ChemistryAuthor(s): Mei Wang, Jing Zhao, Fufang Su, Hui XuAbstractIn this work, our calculations show the Watson-Crick base pairs remain stable through ring-expansion modification. DFT calculations reveal the optimized structures and novel electromagnetic properties of the designed base pairs. It is found the optimized structures possess open-shell singlet ground states except for [yGC]2+ and [yyGC]2+. They exhibit variable degrees of magnetic exchange interaction. As the size of adenine increases, [yAT]2+ and [yyAT]2+ exhibit stronger ant...
Source: Computational and Theoretical Chemistry - July 21, 2019 Category: Chemistry Source Type: research

Comparative Study of the Chemical Reactivity of Graphene and Boron Nitride Sheets
Publication date: Available online 17 July 2019Source: Computational and Theoretical ChemistryAuthor(s): Pablo A. Denis, Federico IribarneAbstractHerein, we performed a theoretical investigation of the reactivities of graphene and 2D-BN. The results indicate that 2D-BN can display chemistry comparable to that of graphene. As observed experimentally, we found that the addition of carbenes, nitrenes and amines is possible. In addition, [2+2] cycloadditions are more likely to occur on 2D-BN rather than on graphene, while the 1,3 cycloaddition of azomethine ylides is also possible. The nitrogen atoms tend to be less reactive t...
Source: Computational and Theoretical Chemistry - July 18, 2019 Category: Chemistry Source Type: research