Gas phase acidities of organic nitric acid derivatives: New opportunities in superacid chemistry
Publication date: Available online 11 April 2019Source: Computational and Theoretical ChemistryAuthor(s): Hamid Saeidian, Sarvin Mashhadian, Zohreh Mirjafary, Morteza RouhaniAbstractDensity functional theory (DFT) calculations have been conducted on a new series of hybrid inorganic-organic acids. One of the oxygen double bonded to nitrogen in nitric acid has been systematically substituted with the different groups such as cyclopentadiene, indene, and borole motifs and the acidity of the compounds has been estimated via the DFT-B3LYP/6-311++G(d, p) method. The compounds 2b and 8 have the highest acidity, within the level o...
Source: Computational and Theoretical Chemistry - April 11, 2019 Category: Chemistry Source Type: research

TCA Self-assembled Fluorescence Probe for Cu (II) Ion Based on the Unique Configuration of Extra Nuclear Electrons of Metal Ions: A TDDFT Study
Publication date: Available online 10 April 2019Source: Computational and Theoretical ChemistryAuthor(s): Fujun Li, Rongjian Sa, Xueying SongAbstractA molecule fluorescence probe of a new ON-OFF type, used for detecting transition metal ions, reported recently, is self-assembled by thiacalix[4]arene(TCA) molecules, micelles and a fluorescence group. It only presents high selectivity for Cu2+ ions, in a solution with the coexistence of Zn2+, Ni2+, Hg2+, Cu2+ Cd2+ ions. Since the mechanism of the ON-OFF signal response of such self-assembled micelle probes has always been a controversial issue of uncertainty, the mechanisms ...
Source: Computational and Theoretical Chemistry - April 10, 2019 Category: Chemistry Source Type: research

Density Functional Theory Analysis for the Limitations of Fluoranthene-Fused Imide Based Small Molecule Acceptor Materials in Photovoltaic Performance
Publication date: Available online 9 April 2019Source: Computational and Theoretical ChemistryAuthor(s): Li-Na Wu, Hang Yin, Ming-Yang Li, Guang-Yan Sun, Guang-De JinAbstractRecently, the bulk-heterojunction (BHJ) organic photovoltaic cells (OPVs) have attracted more attention owing to their potentials in low-weight, cost-effective, semi-transparent, colorful, and flexible. As one of the most promising candidates non-fullerene small molecule acceptors (SMA) in BHJ OPVs, fluoranthene-fused imide (FFI) derivatives can effectively regulate energy level and absorption by functional modification of active sites on its backbone....
Source: Computational and Theoretical Chemistry - April 10, 2019 Category: Chemistry Source Type: research

Preface
Publication date: Available online 6 April 2019Source: Computational and Theoretical ChemistryAuthor(s): Chantal Daniel (Source: Computational and Theoretical Chemistry)
Source: Computational and Theoretical Chemistry - April 8, 2019 Category: Chemistry Source Type: research

Editorial Board
Publication date: 1 May 2019Source: Computational and Theoretical Chemistry, Volume 1155Author(s): (Source: Computational and Theoretical Chemistry)
Source: Computational and Theoretical Chemistry - April 6, 2019 Category: Chemistry Source Type: research

The theoretical investigation on the properties of fluorine-substituted uracil
Publication date: Available online 5 April 2019Source: Computational and Theoretical ChemistryAuthor(s): Min Zhang, Jinfang Xu, Xinming WangAbstractAn investigation was conducted of Fluorine-substituted uracils (5-fluorouracil, 6-fluorouracil and 5, 6-difluoro-uracil) at the B3LYP [6-311G(d, p) / 6-311+G(d, p) / 6-311++G(d, p)] levels. A calculation was performed of their equilibrium structures and harmonic frequencies in gas and water. A combination of C-F binding energies, Natural bond orbital (NBO), reactivity descriptors, Fukui functions, and aromaticity was applied to figure out the impact made by the numbers and loca...
Source: Computational and Theoretical Chemistry - April 5, 2019 Category: Chemistry Source Type: research

Local structure and vibrational properties of molten lead halides PbX2 (X = Cl, Br, I) from ab initio molecular dynamics
Publication date: 15 May 2019Source: Computational and Theoretical Chemistry, Volume 1156Author(s): Dmitry Zakiryanov, Nikolai TkachevAbstractAb initio molecular dynamics (AIMD) was applied to calculate the local structure and dynamics parameters of molten lead halides PbX2 (X = Cl, Br, I). The thoroughness of our approach is substantiated by the variation of both cell size and temperature. The total duration of AIMD runs amounted to 600 ps. It was found that molten lead chlorides exhibit weak binding of the local structure. The latter was analyzed by means of radial distribution functions for each pair of salt const...
Source: Computational and Theoretical Chemistry - April 5, 2019 Category: Chemistry Source Type: research

Corrigendum to “Lin@Tetracyanoethylene (n = 1–4) systems: Lithium salt vs lithium electride” [Comput. Theor. Chem. 1149 (2019) 17–23]
Publication date: 15 May 2019Source: Computational and Theoretical Chemistry, Volume 1156Author(s): Navid Salehi, Ladan Edjlali, Esmail Vessally, Ibon Alkorta, Moosa Es'haghi (Source: Computational and Theoretical Chemistry)
Source: Computational and Theoretical Chemistry - April 5, 2019 Category: Chemistry Source Type: research

Effect of cavity size on the adsorption of small molecules on two isoreticular cobalt-based MOF: An ONIOM approach
Publication date: 15 May 2019Source: Computational and Theoretical Chemistry, Volume 1156Author(s): Jacqueline Calderón, Rafael Añez, Paola AlejosAbstractThe interaction of CO2, CO, H2O, N2, N2O and O2 with the isoreticular metal-organic frameworks [Co(bdc)(pz)]n and [Co(bdc)(bpy)]n was studied. The ONIOM (M06/6-31G(d)HF/6-31G(d)) was applied to determine the structural and thermodynamic changes produced by the interaction among these small molecules and the framework structures. All the calculated adsorption energies are in the range of van der Waals non-covalent interactions, both influenced by dipole-quadr...
Source: Computational and Theoretical Chemistry - April 3, 2019 Category: Chemistry Source Type: research

TDDFT Investigation of Electronic and Optical Properties of Diaryl-substituted Naphtho[1,2-d:5,6-d′]bis-(oxaphosphole) Compounds
Publication date: Available online 30 March 2019Source: Computational and Theoretical ChemistryAuthor(s): Heehyun Baek, Joonghan KimAbstractDensity functional theory (DFT) and time-dependent DFT calculations using the CAM-B3LYP functional were performed to investigate the electronic and optical properties of 2,7-Ph2-naphtho[1,2-d:5,6-d′]bis-(oxaphosphole) (Ph2-NBOP). Furthermore, we examined the effect of several structural modifications of Ph2-NBOP on the energy gap between the highest occupied and lowest unoccupied molecular orbital (HOMO and LUMO, respectively). The HOMO-LUMO gap (ΔEH-L) can be tuned by cont...
Source: Computational and Theoretical Chemistry - March 31, 2019 Category: Chemistry Source Type: research

Editorial Board
Publication date: 15 April 2019Source: Computational and Theoretical Chemistry, Volume 1154Author(s): (Source: Computational and Theoretical Chemistry)
Source: Computational and Theoretical Chemistry - March 31, 2019 Category: Chemistry Source Type: research

Local structure and vibrational properties of molten lead halides PbX2 (X=Cl, Br, I) from ab initio molecular dynamics
Publication date: Available online 29 March 2019Source: Computational and Theoretical ChemistryAuthor(s): Dmitry Zakiryanov, Nikolai TkachevAbstractAb initio molecular dynamics (AIMD) was applied to calculate the local structure and dynamics parameters of molten lead halides PbX2 (X = Cl, Br, I). The thoroughness of our approach is substantiated by the variation of both cell size and temperature. The total duration of AIMD runs amounted to 600 ps. It was found that molten lead chlorides exhibit weak binding of the local structure. The latter was analyzed by means of radial distribution functions for each pair of salt const...
Source: Computational and Theoretical Chemistry - March 30, 2019 Category: Chemistry Source Type: research

Stereo-dynamics of the reaction C + SH(D,T)(v = 0, j = 0) → H(D,T) + CS based on a recent excited state potential energy surface
Publication date: 1 May 2019Source: Computational and Theoretical Chemistry, Volume 1155Author(s): Da-Guang Yue, Lu-Lu Zhang, Juan Zhao, Yu-Zhi Song, Qing-Tian MengAbstractThe isotopic substitution effect on title reactions based on a recently developed potential energy surface of the HCS(A2A″) is studied by the quasi-classical trajectory method. The total integral cross sections (ICSs) and rate constant are presented for C + SH(D,T) → H(D,T) + CS reactions, while the vibrational state resolved ICSs, differential cross sections(DCSs), as well as two angle distribution functions P(θr), P(Φr)...
Source: Computational and Theoretical Chemistry - March 30, 2019 Category: Chemistry Source Type: research

of cavity size on the adsorption of small molecules on two isoreticular cobalt-based MOF: An ONIOM Approach
Publication date: Available online 28 March 2019Source: Computational and Theoretical ChemistryAuthor(s): Jacqueline Calderón, Rafael Añez, Paola AlejosAbstractThe interaction of CO2, CO, H2O, N2, N2O and O2 with the isoreticular metal-organic frameworks [Co(bdc)(pz)]n and [Co(bdc)(bpy)]n was studied. The ONIOM (M06/6-31G(d)HF/6-31G(d)) was applied to determine the structural and thermodynamic changes produced by the interaction among these small molecules and the framework structures. All the calculated adsorption energies are in the range of van der Waals non-covalent interactions, both influenced by dipole...
Source: Computational and Theoretical Chemistry - March 30, 2019 Category: Chemistry Source Type: research

Stereo-dynamics of the reaction C+SH(D,T)(v=0, j=0) →H(D,T) +CS based on a recent excited state potential energy surface
Publication date: Available online 27 March 2019Source: Computational and Theoretical ChemistryAuthor(s): Da-Guang Yue, Lu-Lu Zhang, Juan Zhao, Yu-Zhi Song, Qing-Tian MengAbstractThe isotopic substitution effect on title reactions based on a recently developed potential energy surface of the HCS(A2A″) is studied by the quasi-classical trajectory method. The total integral cross sections (ICSs) and rate constant are presented for C+SH(D,T)→H(D,T)+CS reactions, while the vibrational state resolved ICSs, differential cross sections(DCSs), as well as two angle distribution functions P(θr), P(Φr) of product...
Source: Computational and Theoretical Chemistry - March 28, 2019 Category: Chemistry Source Type: research

Computational study of electronic and optical properties of p-group atomic adsorption on α-Al2O3 (0001)
We present a study on the adsorption process of p-group atoms on the α-Al2O3 corundum phase (0001) surface by the density functional theory. The band gap is tuneable from an insulator to wide bandgap semiconducting nature by adsorption of p-group atoms (B, C, N, O, F) owing physisorption and chemisorption process on the alumina (0001) surface. Adsorption energies are also calculated for all complex systems for centre top, Al-top and O-top sites. The hybridization of adsorbed p-group atoms, tune the electronic properties along to the n-type and p-type nature, which light up the new way to develop possible nanodevice. ...
Source: Computational and Theoretical Chemistry - March 28, 2019 Category: Chemistry Source Type: research

High-level theoretical study of the hydrogen abstraction reaction H2S + O2 = SH + HO2 and prediction of the rate constants
Publication date: 1 May 2019Source: Computational and Theoretical Chemistry, Volume 1155Author(s): Quan-De Wang, Mao-Mao Sun, Jin-Hu LiangAbstractHydrogen abstraction reaction of hydrogen sulfide (H2S) by molecule oxygen (O2) forming hydroperoxyl radical (HO2) and hydrosulfide radical (SH) is very important for both atmospheric and combustion chemistry. This work reports a systematic theoretical study on this reaction using a combination of high-level quantum chemistry methods and chemical kinetic theory. Geometry optimizations for all species are performed at QCISD/cc-pVQZ level of theory. The energies for minima and tran...
Source: Computational and Theoretical Chemistry - March 28, 2019 Category: Chemistry Source Type: research

Density functional theory study of the CO adsorption on Ni4M (M = Mo, Sc, and Y) nanoclusters
In this study, the nondissociative CO adsorption on the bimetallic clusters of Ni4M (M = Mo, Sc, Y) have been investigated using density functional theory. Different adsorption mode are considered and 9 stable Ni4M-CO complex are resulted for each Ni4M nanoclusters. We found that CO adsorption is thermodynamically favorable on the clusters and the average adsorption energies of optimized geometries are −42, −35 and −33 kcal/mol for Ni4Mo, Ni4Sc and Ni4Y clusters, respectively. Also, the maximum adsorption energies are found to be −67, −53 and −47 kcal/mol for Ni4Mo, Ni4Sc and Ni4...
Source: Computational and Theoretical Chemistry - March 26, 2019 Category: Chemistry Source Type: research

QM/MM Nonadiabatic Dynamics Simulation on Ultrafast Excited-State Relaxation in Osmium(II) Compounds in Solution
Publication date: Available online 23 March 2019Source: Computational and Theoretical ChemistryAuthor(s): Ye-Guang Fang, Ling-Ya Peng, Xiang-Yang Liu, Wei-Hai Fang, Ganglong CuiAbstractPhotoinduced excited-state relaxation dynamics of organometallic compounds, due to their potential applications in solar cells, organic light-emitting diodes, photocatalysis, etc., have been recently explored by a wealth of ultrafast experimental techniques. However, the corresponding nonadiabatic dynamics simulations are rarely reported. In this work, the early-time excited-state relaxation dynamics of two Os(II) compounds i.e. Os(bpy)3 and...
Source: Computational and Theoretical Chemistry - March 23, 2019 Category: Chemistry Source Type: research

Automated reaction path search calculations of spin-inversion mechanisms in the 6,4,2Nb + C2H4 reaction
Publication date: 1 May 2019Source: Computational and Theoretical Chemistry, Volume 1155Author(s): Masahiro Kawano, Shoichi Koido, Taiki Nakatomi, Yuya Watabe, Toshiyuki TakayanagiAbstractThe mechanisms of CH bond activation in C2H4 by 6,4,2Nb metal atom have been systematically investigated using the automated reaction path search calculation with the mixed-spin Hamiltonian model. It is found that the most stable 4NbC2H2 + H2 products are formed from the 6Nb + C2H4 reactants on the sextet, quartet, and double potential energy surfaces via multiple spin-inversion (intersystem crossing) points, which are mostly asso...
Source: Computational and Theoretical Chemistry - March 23, 2019 Category: Chemistry Source Type: research

Density Functional Theory Study of the CO Adsorption on Ni4M (M= Mo, Sc, and Y) Nanoclusters
In this study, the nondissociative CO adsorption on the bimetallic clusters of Ni4M (M=Mo, Sc, Y) have been investigated using density functional theory. Different adsorption mode are considered and 9 stable Ni4M-CO complex are resulted for each Ni4M nanoclusters. We found that CO adsorption is thermodynamically favorable on the clusters and the average adsorption energies of optimized geometries are -42, -35 and -33 kcal/mol for Ni4Mo, Ni4Sc and Ni4Y clusters, respectively. Also, the maximum adsorption energies are found to be -67, -53 and -47 kcal/mol for Ni4Mo, Ni4Sc and Ni4Y, respectively. The most stable complexes obt...
Source: Computational and Theoretical Chemistry - March 22, 2019 Category: Chemistry Source Type: research

A study of the basis set dependence of the bifunctional expression of the non-interacting kinetic energy for atomic systems
In this study the atoms from H - Xe are examined, showing that the energy deviation between the bifunctional expression and the orbital-based kinetic energy density is of a few hundred millihartrees for a quadruple basis set, while it can reach the order of a few hartrees when employing basis sets of less quality.Graphical abstract (Source: Computational and Theoretical Chemistry)
Source: Computational and Theoretical Chemistry - March 22, 2019 Category: Chemistry Source Type: research

High-level theoretical study of the hydrogen abstraction reaction H2S + O2 = SH + HO2 and prediction of the rate constants
Publication date: Available online 20 March 2019Source: Computational and Theoretical ChemistryAuthor(s): Quan-De Wang, Mao-Mao Sun, Jin-Hu LiangAbstractHydrogen abstraction reaction of hydrogen sulfide (H2S) by molecule oxygen (O2) forming hydroperoxyl radical (HO2) and hydrosulfide radical (SH) is very important for both atmospheric and combustion chemistry. This work reports a systematic theoretical study on this reaction using a combination of high-level quantum chemistry methods and chemical kinetic theory. Geometry optimizations for all species are performed at QCISD/cc-pVQZ level of theory. The energies for minima a...
Source: Computational and Theoretical Chemistry - March 22, 2019 Category: Chemistry Source Type: research

Computational study of the [(CO)2(benzoate)MII/III(terephthalate)]0/1+ complexes with M = V, Cr, Mn, Fe and Co
Publication date: 1 May 2019Source: Computational and Theoretical Chemistry, Volume 1155Author(s): Hossein Shirani, Hassan SabzyanAbstractComputational study at DFT-B3LYP/LANL2DZ level of theory is carried out to evaluate structural, bonding and energetic characteristics of cis/trans isomers of the [(CO)2(benzoate)MII/III(terephthalate)]0/1+ complexes with 3d transition metals M = V, Cr, Mn, Fe and Co. Results of this study show that all cis/trans isomers of these complexes in their two oxidation states are stable with distinctly different structures. As a general trend, for all cis/trans isomers of these complexes, th...
Source: Computational and Theoretical Chemistry - March 22, 2019 Category: Chemistry Source Type: research

Possible low-energy isomers of OHn(H2O)4 (n = 0, ±1) clusters via the particle swarm optimization algorithm: An ab initio study
Publication date: 1 May 2019Source: Computational and Theoretical Chemistry, Volume 1155Author(s): Yi-Ming Wen, Zhao-Qi Wang, Cui-E Hu, Xiang-Rong Chen, Qi-Feng ChenAbstractThe possible low-energy structures of the anionic, neutral, and cationic water clusters OHn(H2O)4 (n = 0, ±1) were investigated using the particle swarm optimization algorithm together with ab initio calculations. Geometry optimization and vibrational analysis for possible low-lying water clusters were conducted at the MP2/aug-cc-pVDZ level and further verified at the CCSD(T)/aug-cc-pVTZ level. The results revealed obvious structural differen...
Source: Computational and Theoretical Chemistry - March 22, 2019 Category: Chemistry Source Type: research

Possible low-energy isomers of OHn(H2O)4 (n=0, ±1) clusters via the particle swarm optimization algorithm: An ab initio study
Publication date: Available online 19 March 2019Source: Computational and Theoretical ChemistryAuthor(s): Yi-Ming Wen, Zhao-Qi Wang, Cui-E Hu, Xiang-Rong Chen, Qi-Feng ChenAbstractThe possible low-energy structures of the anionic, neutral, and cationic water clusters OHn(H2O)4 (n=0, ±1) were investigated using the particle swarm optimization algorithm together with ab initio calculations. Geometry optimization and vibrational analysis for possible low-lying water clusters were conducted at the MP2/aug-cc-pVDZ level and further verified at the CCSD(T)/aug-cc-pVTZ level. The results revealed obvious structural differe...
Source: Computational and Theoretical Chemistry - March 21, 2019 Category: Chemistry Source Type: research

Automated reaction path search calculations of spin-inversion mechanisms in the 6,4,2Nb + C2H4 reaction
Publication date: Available online 19 March 2019Source: Computational and Theoretical ChemistryAuthor(s): Masahiro Kawano, Shoichi Koido, Taiki Nakatomi, Yuya Watabe, Toshiyuki TakayanagiAbstractThe mechanisms of C-H bond activation in C2H4 by 6,4,2Nb metal atom have been systematically investigated using the automated reaction path search calculation with the mixed-spin Hamiltonian model. It is found that the most stable 4NbC2H2 + H2 products are formed from the 6Nb + C2H4 reactants on the sextet, quartet, and double potential energy surfaces via multiple spin-inversion (intersystem crossing) points, which are mostly asso...
Source: Computational and Theoretical Chemistry - March 19, 2019 Category: Chemistry Source Type: research

Analytical calculations of thermodynamic functions of lithium dimer using modified Tietz and Badawi-Bessis-Bessis potentials
Publication date: Available online 19 March 2019Source: Computational and Theoretical ChemistryAuthor(s): R. Khordad, A. GhanbariAbstractWe have analytically solved the Klein-Gordon (KG) equation for two different potentials. We have used the modified Tietz (MT) and the Badawi-Bessis-Bessis (BBB) diatomic molecular potentials and derived the analytical expressions for the energy spectra. Then, we have analytically obtained the thermodynamic functions for a3Σu+ state of the 7Li2 molecule using the two potentials. For this goal, we have calculated the partition function, mean energy, specific heat, and entropy of the m...
Source: Computational and Theoretical Chemistry - March 19, 2019 Category: Chemistry Source Type: research

Understanding Hydroxide Reactions with Guanidinium-based Anion Exchange Polymers Under Conditions Relevant to Bipolar Membrane Electrodialysis
Publication date: Available online 18 March 2019Source: Computational and Theoretical ChemistryAuthor(s): James Farrell, Rodrigo J. MartínezAbstractAnion exchange polymers are susceptible to loss of cationic functionality as a result of nucleophilic attack by hydroxide ions. This research investigated the stability of two guanidinium-based cations as anion exchange functional groups under conditions relevant to bipolar membrane electrodialysis. Density functional theory simulations were performed to investigate reaction energies and activation barriers for reactions of hydroxide ions with pentamethylguanidinium (PMG...
Source: Computational and Theoretical Chemistry - March 18, 2019 Category: Chemistry Source Type: research

Electronic structure of merocyanine dyes derived from 3H-indole and malononitrile in the ground and excited states: DFT/TD-DFT analysis
Publication date: Available online 16 March 2019Source: Computational and Theoretical ChemistryAuthor(s): Andrii V. Kulinich, Alexander A. IshchenkoAbstractThe electronic structure and spectral-fluorescent properties of vinylogous positively solvatochromic merocyanines have been studied within the four-level scheme of electronic states using the DFT and TD-DFT computations. The calculations with the solvation taken into account have allowed us to interpret some non-trivial aspects of the merocyanine solvatochromism: weakening of the solvent influence in the fluorescent state, dependence of the shape and width of the spectr...
Source: Computational and Theoretical Chemistry - March 18, 2019 Category: Chemistry Source Type: research

Study on the spectral complementary composite dye molecules designed for high performance Dye-sensitized solar cells: A theoretical investigation
We present the theoretical investigation on absorption wavelength complementarity organic dyes for dye-sensitized solar cell application. Our results show that B1 dye have the best absorption wavelength complementarity with XY1 dye, and correspondingly induces higher light-harvesting efficiency in the range of 350-450 nm of the solar spectrum. (Source: Computational and Theoretical Chemistry)
Source: Computational and Theoretical Chemistry - March 18, 2019 Category: Chemistry Source Type: research

A XMS-CASPT2 non-adiabatic dynamics study on pyrrole
Publication date: Available online 14 March 2019Source: Computational and Theoretical ChemistryAuthor(s): Moritz Heindl, Leticia GonzálezAbstractThe photoinduced dynamics of pyrrole is revisited employing the independent trajectory surface hopping methodology based on extended multi-state second order perturbation theory (XMS-CASPT2). Excitation at 200 nm into a high density of states region gives rise to ultrafast deactivation via internal conversion. The primary dissociation channel was found to be N-H hydrogen abstraction, resulting in pyrrolyl radical formation. The associated time constant for hydrogen dissocia...
Source: Computational and Theoretical Chemistry - March 15, 2019 Category: Chemistry Source Type: research

Diabatic pseudofragmentation and nonadiabatic excitation-energy transfer in meta-substituted dendrimer building blocks
Publication date: Available online 15 March 2019Source: Computational and Theoretical ChemistryAuthor(s): Emmeline K.-L. Ho, Benjamin LasorneAbstractExcitation-energy transfer in multichromophoric assemblies is often pictured in terms of excitonic models whereby the underlying diabatic states correlate with the ground (acceptor) and excited (donnor) electronic states of well-defined separated fragments. Poly(phenylene ethynylene) dendrimers also exhibit ultrafast unidirectional excitation-energy transfer; however, the definition of the fragments is no longer straightforward, as adjacent chromophores share a common meta-sub...
Source: Computational and Theoretical Chemistry - March 15, 2019 Category: Chemistry Source Type: research

Renner-Teller and pseudo-Renner-Teller interactions in the electronic ground and excited states of the dicyanoacetylene radical cation: Assignment of vibronic spectrum and elucidation of nonradiative and radiative decay mechanisms
Publication date: Available online 13 March 2019Source: Computational and Theoretical ChemistryAuthor(s): Arpita Ghosh, Karunamoy Rajak, Arun Kumar Kanakati, S. MahapatraAbstractVibronic interactions in the first five energetically lowest electronic states (X∼2Πu - A∼2Σg+ -B∼2Σu+ -C∼2Πg -D∼2Πu) of dicyanoacetylene radical cation (C4N2·+) and their effect on the nuclear dynamics are examined in this article. The spectroscopy of C4N2·+ is a subject of outstanding complexity and addressed by the [see, the recent article, J. Chem. Phys. 139, 184304 (2013)]. The energetic o...
Source: Computational and Theoretical Chemistry - March 15, 2019 Category: Chemistry Source Type: research

Extended Born-Oppenheimer Equations for Non-Abelian Situations: A Study on NO3 Radical and 1,3,5-C6H3F3+ Radical Cation
Publication date: Available online 14 March 2019Source: Computational and Theoretical ChemistryAuthor(s): Soumya Mukherjee, Bijit Mukherjee, Subhankar Sardar, Satrajit AdhikariAbstractFormulation of single-surface extended Born-Oppenheimer (EBO) equation is a long-standing problem for three or higher dimensional sub-Hilbert space mainly due to the difficulty to include the contribution of off-diagonal elements of anti-symmetric nonadiabatic coupling matrix (τ→) as the diagonal ones. Diagonalization of a vector matrix is possible only when its components commute with each other (i.e. curl τ→=0→) and t...
Source: Computational and Theoretical Chemistry - March 15, 2019 Category: Chemistry Source Type: research

DFT study on the mechanistic details of the hydrolysis of dicyan using acetaldehyde as the first organocatalyst
Publication date: Available online 14 March 2019Source: Computational and Theoretical ChemistryAuthor(s): Hossein Tavakol, Mohammad A. Ranjbari, Amir MahmoudiAbstractThe possible mechanistic pathways for acetaldehyde-catalyzed hydrolysis of dicyan have been investigated. Five routes, starting from simultaneous addition of acetaldehyde and water to dicyan (a), conversion of acetaldehyde to its hydrated form (b), addition of acetaldehyde (only) to dicyan (c), water-assisted hydrolysis of dicyan, without using acetaldehyde (d) and enolization of acetaldehyde (e) have been studied with details. The order of the overall barrier...
Source: Computational and Theoretical Chemistry - March 15, 2019 Category: Chemistry Source Type: research

Thermodynamic stability and pressure dependence of FePO4 Polymorphs
Publication date: Available online 9 March 2019Source: Computational and Theoretical ChemistryAuthor(s): N.L. Lethole, H.R. Chauke, P.E. NgoepeAbstractOlivine LiFePO4 is a promising cathode material for lithium ion batteries. Its delithiated form FePO4 has attracted interest as potential cathode for rechargeable lithium ion batteries due to high charge/discharge capacity and low cost. This paper report pressure dependence DFT+U calculations and stability of FePO4 polymorphs. The heats of formation predict that berlinite polymorph is thermodynamically stable up to 4 GPa, while HP phase reaches a transition above 4 GPa at 0 ...
Source: Computational and Theoretical Chemistry - March 11, 2019 Category: Chemistry Source Type: research

Structural, magnetic and electronic properties of CunNi55−n (n = 0–55) nanoparticles: Combination artificial bee colony algorithm with DFT
Publication date: 15 April 2019Source: Computational and Theoretical Chemistry, Volume 1154Author(s): Yan Sun, Shanggou Liu, Xiangyu Guo, Shiping HuangAbstractThe structures of CunNi55−n (n = 0–55) nanoparticles are generated by artificial bee colony algorithm, and the structural, magnetic and electronic properties of the CunNi55−n nanoparticles are performed by the density functional theory calculation. The calculation results show that the core-shell structure Cu42Ni13 is the most stable structure of all CunNi55−n NPs, besides, the Cu atoms prefer to appear on the surface and the Ni atoms pref...
Source: Computational and Theoretical Chemistry - March 11, 2019 Category: Chemistry Source Type: research

Clustering of H2SO4 with BX3 (X = H, F, Cl, Br, CN, OH) compounds creates strong acids and superacids
Publication date: 1 April 2019Source: Computational and Theoretical Chemistry, Volume 1153Author(s): Younes Valadbeigi, Theo KurténAbstractThe interaction of H2SO4 with boron compounds including BH3, BF3, BCl3, BBr3, B(CN)3 and B(OH)3 was studied computationally using the ωB97xD density functional. All the BX3 compounds except B(OH)3 bind to H2SO4 via both SOH…X hydrogen bonds, and interactions between the B atoms and the SO oxygen atoms. B(OH)3 interacts with H2SO4 solely through hydrogen bonds. B(CN)3 and BCl3 exhibit the strongest and weakest interactions with H2SO4, respectively. Natural bond orbita...
Source: Computational and Theoretical Chemistry - March 9, 2019 Category: Chemistry Source Type: research

Structural, magnetic and electronic properties of CunNi55-n (n=0~55) nanoparticles: Combination artificial bee colony algorithm with DFT
Publication date: Available online 7 March 2019Source: Computational and Theoretical ChemistryAuthor(s): Yan Sun, Shanggou Liu, Xiangyu Guo, Shiping HuangAbstractThe structures of CunNi55-n (n=0~55) nanoparticles are generated by artificial bee colony algorithm, and the structural, magnetic and electronic properties of the CunNi55-n nanoparticles are performed by the density functional theory calculation. The calculation results show that the core-shell structure Cu42Ni13 is the most stable structure of all CunNi55-n NPs, besides, the Cu atoms prefer to appear on the surface and the Ni atoms prefer to occupy the interior...
Source: Computational and Theoretical Chemistry - March 8, 2019 Category: Chemistry Source Type: research

Understanding the spontaneous formation of pyridofuroxan from 2-azido-3-nitropyridine: A theoretical evaluation
Publication date: Available online 7 March 2019Source: Computational and Theoretical ChemistryAuthor(s): Sarai Vega-Rodríguez, Rogelio Jiménez-Cataño, Elisa LeyvaAbstractPyridofuroxans are analogous to benzofuroxans; they present similar properties and may be synthesized in similar ways. However, when they are prepared from o-nitropyridinazides, they do not need energy to be synthesized, in contrast to benzofuroxans which require heat or light. In order to understand this phenomenon, a DFT study about the mechanism of pyridofuroxan formation from a series of substituted o-nitropyridinazides (2-azido-3-...
Source: Computational and Theoretical Chemistry - March 8, 2019 Category: Chemistry Source Type: research

First-principle study on the conductance of benzene-based molecules with various bonding characteristics
Publication date: Available online 7 March 2019Source: Computational and Theoretical ChemistryAuthor(s): Yuanyuan He, Na Cheng, Jianwei ZhaoAbstractElectron transport through benzene-based molecule is the fundamental issue of the electrical properties of graphene and other conjugated π-systems. To improve the device performance of conjugated π-systems, we designed a series of benzene models and analyzed the effect of bonding environments on the molecular conductance of benzene. By combing density functional theory and the non-equilibrium Green’s function method, it is found that the conductance of isolated benz...
Source: Computational and Theoretical Chemistry - March 8, 2019 Category: Chemistry Source Type: research

Interaction and damage of nucleobases of DNA and RNA caused by silicon nanoparticle and crystalline silica: First principles Study
Publication date: Available online 7 March 2019Source: Computational and Theoretical ChemistryAuthor(s): Haider Abbas, Deepti Maikhuri, Charu SharmaAbstractWe use density functional theory (DFT) to report the interaction of silicon nanoparticle and crystalline silica with the nucleobases of DNA/RNA-adenine (A), guanine (G), cytosine (C), thymine (T) and uracil (U). We obtain and analyse the binding energies, structural parameters and charge transfer to determine the strength between silicon cluster/quartz and nucleobases. The results show that the strength of the silicon cluster interaction with the nucleobases molecules f...
Source: Computational and Theoretical Chemistry - March 8, 2019 Category: Chemistry Source Type: research

Solvent effect on Hetero-Diels-Alder reaction of isoselenazole with symmetrical acetylenic dienophiles: A MEDT study
Publication date: Available online 7 March 2019Source: Computational and Theoretical ChemistryAuthor(s): Abdelilah BenallouAbstractA theoretical investigation study by the molecular electron density theory (MEDT) of the role of solvent toluene in the Hetero-Diels-Alder (HDA) reaction of isoselenazole with symmetrical acetylenic dienophiles is carried out, and also a comparative study was performed. The high activation energy involved in this reaction implies a not facile reaction. Whereas, ELF shows a missed pseudoradical formation at the N2 nitrogen atom of isoselenazole moiety increases the possibility of not formation o...
Source: Computational and Theoretical Chemistry - March 8, 2019 Category: Chemistry Source Type: research

Clustering of H2SO4 with BX3 (X=H, F, Cl, Br, CN,OH) compounds creates strong acids and superacids
Publication date: Available online 5 March 2019Source: Computational and Theoretical ChemistryAuthor(s): Younes Valadbeigi, Theo KurténAbstractThe interaction of H2SO4 with boron compounds including BH3, BF3, BCl3, BBr3, B(CN)3 and B(OH)3 was studied computationally using the ωB97xD density functional. All the BX3 compounds except B(OH)3 bind to H2SO4 via both SOH...X hydrogen bonds, and interactions between the B atoms and the S=O oxygen atoms. B(OH)3 interacts with H2SO4 solely through hydrogen bonds. B(CN)3 and BCl3 exhibit the strongest and weakest interactions with H2SO4, respectively. Natural bond orbita...
Source: Computational and Theoretical Chemistry - March 6, 2019 Category: Chemistry Source Type: research

Non-adiabatic dynamics combining Ehrenfest, decoherence, and multiscale approaches applied to ionic rare-gas clusters photodissociation, post-ionization fragmentation, and collisions
Publication date: Available online 4 March 2019Source: Computational and Theoretical ChemistryAuthor(s): René Kalus, Ivan Janeček, Florent Xavier GadéaAbstractMethodological approaches for realistic modeling of non-adiabatic processes are reviewed and selected applications are discussed. The methods are based on a hybrid approach with heavy atomic nuclei treated classically and light electrons described quantum mechanically. The core of the methodology consists in Ehrenfest’s mean-field approach enhanced by a model inclusion of quantum decoherence. Approximate treatment of long-time evolutions is also ...
Source: Computational and Theoretical Chemistry - March 5, 2019 Category: Chemistry Source Type: research

Computational study of the [(CO)2(benzoate)MII/III(terephthalate)]0/1+ complexes with M = V, Cr, Mn, Fe and Co
Publication date: Available online 2 March 2019Source: Computational and Theoretical ChemistryAuthor(s): Hossein Shirani, Hassan SabzyanAbstractComputational study at DFT-B3LYP/LANL2DZ level of theory is carried out to evaluate structural, bonding and energetic characteristics of cis/trans isomers of the [(CO)2(benzoate)MII/III(terephthalate)]0/1+ complexes with 3d transition metals M = V, Cr, Mn, Fe and Co. Results of this study show that all cis/trans isomers of these complexes in their two oxidation states are stable with distinctly different structures. As a general trend, for all cis/trans isomers of these comple...
Source: Computational and Theoretical Chemistry - March 4, 2019 Category: Chemistry Source Type: research

Atoms and Bonds in Molecules: Molecular Radial Energy Densities
Publication date: Available online 2 March 2019Source: Computational and Theoretical ChemistryAuthor(s): Ibrahim E. Awad, Raymond A. PoirierAbstractThe molecular radial density (ρrad) serves as a powerful tool to partition molecules into: non-bonding, core, and bonding regions. Similar to ρrad, a method is presented where both forms of the radial kinetic, exchange, Coulomb, and electron-nuclear potential energy densities are plotted on a mesh. As far as we are aware, this is the first time expressions for energy densities have been presented. Such plots provide an alternative approach to understanding the physics a...
Source: Computational and Theoretical Chemistry - March 4, 2019 Category: Chemistry Source Type: research

“Hypervalency” and the Chemical Bond
Publication date: Available online 25 February 2019Source: Computational and Theoretical ChemistryAuthor(s): Apostolos Kalemos, Isuru R. Ariyaranthna, Shahriar N. Khan, Evangelos Miliordos, Aristides MavridisAbstractBonding in chemistry refers to the stability of molecules, therefore it is of paramount importance to natural sciences and certainly to all aspects of life. Yet bonding is a chameleon–like fuzzy concept, leaving enough space to the sprouting of a variety of “theories” supposedly explaining the structure and bonding of molecular systems. Admittedly some of these “theoretical ideas” ...
Source: Computational and Theoretical Chemistry - February 26, 2019 Category: Chemistry Source Type: research

Ab Initio Molecular Dynamics Investigation on NaCl Solution at Diluted Concentration
Publication date: Available online 26 February 2019Source: Computational and Theoretical ChemistryAuthor(s): Yun DingAbstractDespite being one of the simplest and extensively studied systems, the origin of how ions influence water still remains elusive. Many previous studies focused on concentrated solutions, where only limited truly bulk water is present. To gain more insights into the nature of ion-water interactions with the presence of truly bulk water, diluted NaCl solution together with single Na+ and single Cl- solutions are investigated by state-of-the-art ab initio molecular dynamics. Structural, dynamical and ele...
Source: Computational and Theoretical Chemistry - February 26, 2019 Category: Chemistry Source Type: research