A DFT study on second-order NLO properties of bis-cyclometalated Iridium(III) complexes with chelating dicarbene auxiliary ligands
Publication date: Available online 11 July 2019Source: Computational and Theoretical ChemistryAuthor(s): Yang Shen, Xiang Li, Jinting Ye, Yongqing QiuAbstractIridium cyclometalated complexes with excellent nonlinear optical (NLO) properties in photophysical and redox properties have attracted considerable attention. The aim of this paper is calculate and analyze the redox effect on geometrical structures, UV-vis absorption spectra and second-order nonlinear optical (NLO) properties. The results show that the bis-cyclometalated Iridium(III) complexes have larger static first hyperpolarizabilities (βtot) values and they...
Source: Computational and Theoretical Chemistry - July 12, 2019 Category: Chemistry Source Type: research

Ionization dynamics of Ne-doped helium clusters at low temperature: Ring-polymer molecular dynamics simulations including electronically nonadiabatic transitions
Publication date: Available online 11 July 2019Source: Computational and Theoretical ChemistryAuthor(s): Takaaki Miyazaki, Toshiyuki TakayanagiAbstractIonization dynamics of NeHen (n ≤ 100) clusters has been studied by path-integral molecular dynamics (PIMD) and ring-polymer molecular dynamics (RPMD) simulations that can effectively describe nuclear quantum effects. The pairwise-additive interatomic potential model was used for the neutral NeHen clusters while the diatomics-in-molecule (DIM) model including spin-orbit coupling in Ne+(2P) was employed to describe the electronic structures of the cationic NeHen+ clusters....
Source: Computational and Theoretical Chemistry - July 12, 2019 Category: Chemistry Source Type: research

Theoretical study on boron-nitrogen containing analogues of 6,6,18-graphdiyne
Publication date: Available online 9 July 2019Source: Computational and Theoretical ChemistryAuthor(s): Chenna Shi, Zhan Su, Yuanhe HuangAbstractThe structures and electronic properties are explored for the several boron-nitrogen (BN) containing analogues of 6,6,18-graphdiyne including two-dimensional (2D) sheets and one-dimensional (1D) nanoribbons (NRs) using the self-consistent-field crystal orbital method. The frequency analyses reveal the BN-containing materials are stable structures due to no existence of imaginary frequency. The calculations show that BN doped 6,6,18-graphdiyne sheets are semiconductors with wide ba...
Source: Computational and Theoretical Chemistry - July 10, 2019 Category: Chemistry Source Type: research

Editorial Board
Publication date: 15 August 2019Source: Computational and Theoretical Chemistry, Volume 1162Author(s): (Source: Computational and Theoretical Chemistry)
Source: Computational and Theoretical Chemistry - July 7, 2019 Category: Chemistry Source Type: research

Adsorption behavior of cytosine and guanine nucleobases on graphyne nanosheets: a DFT study
Publication date: Available online 5 July 2019Source: Computational and Theoretical ChemistryAuthor(s): S. Madhumitha, V. Nagarajan, R. ChandiramouliAbstractWe explored the cytosine and guanine nitrogenous bases adsorption over pure and boron substituted graphyne (Gpn) nanosheet. Initially, the stability of Gpn nanosheet is ascertained by formation energy and found to be stable. Also, the energy gap and density of states (DOS) spectrum are investigated for isolated condition and cytosine, and guanine adsorbed Gpn nanosheet. The adsorption energy shows physisorption type of adsorption for cytosine and guanine bases on Gpn n...
Source: Computational and Theoretical Chemistry - July 6, 2019 Category: Chemistry Source Type: research

Publisher Note
Publication date: Available online 4 July 2019Source: Computational and Theoretical ChemistryAuthor(s): (Source: Computational and Theoretical Chemistry)
Source: Computational and Theoretical Chemistry - July 4, 2019 Category: Chemistry Source Type: research

Computational studies on the reactions of the peroxy radical CF3OCH2O2 with HO2 and NO
Publication date: 1 September 2019Source: Computational and Theoretical Chemistry, Volume 1163Author(s): Zoi Salta, Stavroula Liaska, Demetrios K. Papayannis, Antonija Lesar, Agnie M. KosmasAbstractComputational studies on the reactions of the peroxy radical, CF3OCH2O2, with the species HO2 and NO in the gas-phase are carried out, using ab initio and density functional theory methods. Formation of CF3OCH2OOH, through the attractive triplet state, is shown to be the dominant pathway in the reaction with HO2. The coupling with NO leads primarily to CF3OCH2O and NO2 through the decomposition of the association nitrite minimum...
Source: Computational and Theoretical Chemistry - July 3, 2019 Category: Chemistry Source Type: research

Comparative DFT study on the platinum catalyzed [3 + 2] and [2 + 2] cycloaddition reactions between the derivatives of allene and alkene
Publication date: 1 September 2019Source: Computational and Theoretical Chemistry, Volume 1163Author(s): Rohini Saha, Arpita Chatterjee, Sonjoy Mondal, Poulami Pal, Kuheli Chakrabarty, Gourab Kanti DasAbstractA comparative study on [3 + 2] and [2 + 2] cycloaddition processes between alkene and allene derivatives, under the catalytic action of platinum salt, has been performed using DFT quantum mechanical method. Our study reveals that the metal bound allenes react through a stepwise pathway with alkene system leading to a tetracyclic or pentacyclic products. The unsubstituted reactants reveal only the [3 + 2] r...
Source: Computational and Theoretical Chemistry - June 30, 2019 Category: Chemistry Source Type: research

Density functional theory study of structural, electronic and CO adsorption properties of anionic Scn- (n = 2-13) clusters
Publication date: Available online 27 June 2019Source: Computational and Theoretical ChemistryAuthor(s): Saira Sajjad, Muhammad Ali Hashmi, Tariq Mahmood, Khurshid AyubAbstractClusters are aggregates or assemblies of atoms and have properties intermediate between bulk and molecules. Among transition metals, the studies regarding scandium cluster and in particular anionic scandium clusters are very scarce. Herein, geometric and electronic properties of anionic scandium clusters Scn- (n = 2-13) are studied by gradient-corrected exchange-correlation functional PBEPBE with LANL2DZ basis set. A number of possible geometries are...
Source: Computational and Theoretical Chemistry - June 28, 2019 Category: Chemistry Source Type: research

A DFT/TDDFT Investigation on Structure–Photophysical Properties Relationship of Phenothiazine Derivatives with Substitutions on C-3/N-10 Sites
Publication date: Available online 27 June 2019Source: Computational and Theoretical ChemistryAuthor(s): Yongqiang Lu, Chuchu Jiang, Xiulan Li, Jian SongAbstractDFT/TDDFT methods were employed to investigate structure–photophysical properties relationship of PTZ derivatives, presenting various popular substituents on common C-3/N-10 active sites. Results indicate that if intramolecular CT pattern or/and high π delocalization appears in these derivatives, it will guide the spectral variation. However, the emission is more sensitive to CT than to the planarity, whereas the reverse is found for absorption. The polari...
Source: Computational and Theoretical Chemistry - June 28, 2019 Category: Chemistry Source Type: research

Computational studies on the reactions of the peroxy radical CF3OCH2O2 .with HO2.and NO
Publication date: Available online 27 June 2019Source: Computational and Theoretical ChemistryAuthor(s): Zoi Salta, Stavroula Liaska, Demetrios K. Papayannis, Antonija Lesar, Agnie M. KosmasAbstractComputational studies on the reactions of the peroxy radical, CF3OCH2O2., with the species HO2. and NO. in the gas-phase are carried out , using ab initio and density functional theory methods. Formation of CF3OCH2OOH, through the attractive triplet state, is shown to be the dominant pathway in the reaction with HO2 . . The coupling with NO. leads primarily to CF3OCH2O. and NO2. through the decomposition of the association nitri...
Source: Computational and Theoretical Chemistry - June 28, 2019 Category: Chemistry Source Type: research

Highly selective acridinium based cyanine dyes for the detection of DNA base pairs (adenine, cytosine, guanine and thymine)
Publication date: Available online 28 June 2019Source: Computational and Theoretical ChemistryAuthor(s): Hasnain Sajid, Khurshid Ayub, Muhammad Arshad, Tariq MahmoodAbstractIn the current study, the DFT calculations are performed to investigate the binding properties of nonsymmetric cyanine dyes (1a, 1b, 1c and 1d) for DNA basis. The effect of change in methine chain between two heterocycles on reactivity is explored through chemical reactivity descriptors (Global) including ionization potential (IP), electron affinity (EA), hardness (η), softness (S), electronegativity (χ) and MEP (molecular electrostatic potentia...
Source: Computational and Theoretical Chemistry - June 28, 2019 Category: Chemistry Source Type: research

Comparative DFT study on the platinum catalyzed [3+2] and [2+2] cycloaddition reactions between the derivatives of allene and alkene
Publication date: Available online 24 June 2019Source: Computational and Theoretical ChemistryAuthor(s): Rohini Saha, Arpita Chatterjee, Sonjoy Mondal, Poulami Pal, Kuheli Chakrabarty, Gourab Kanti DasAbstractA comparative study on [3+2] and [2+2] cycloaddition processes between alkene and allene derivatives, under the catalytic action of platinum salt, have been performed using DFT quantum mechanical method. Our study reveals that the metal bound allenes react through a stepwise pathway with alkene system leading to a tetracyclic or pentacyclic products. The unsubstituted reactants reveal only the [3+2] reaction by crossi...
Source: Computational and Theoretical Chemistry - June 25, 2019 Category: Chemistry Source Type: research

The dataset of covalent bond lengths resulting from the first-principle calculations
Publication date: Available online 24 June 2019Source: Computational and Theoretical ChemistryAuthor(s): Tymofii Yu. Nikolaienko, Valerii S. Chuiko, Leonid A. BulavinAbstractThe non-empirical dataset of the covalent bond lengths is created via the automated procedure combining geometries of 26050 small closed-shell molecules optimized by one of three DFT methods (B3LYP/6-31G*, PBEh-3c, B97-3c) with the covalent bond graphs recovered from the MP2 first-order density matrices by recently introduced property-oriented orbital localization procedure (CLPO). The dataset (https://dx.doi.org/10.5281/zenodo.2631844) contains the di...
Source: Computational and Theoretical Chemistry - June 24, 2019 Category: Chemistry Source Type: research

Ab Initio Chemical Kinetics for Hypergolic Reactions of Nitrogen Tetroxide with Hydrazine and Methyl Hydrazine
Publication date: Available online 20 June 2019Source: Computational and Theoretical ChemistryAuthor(s): Trinh Le Huyen, Putikam Raghunath, M.C. LinAbstractThe kinetics and mechanisms for the hypergolic reactions of N2O4 (NTO) with N2H4 and CH3NHNH2 have been investigated by ab initio molecular orbital theory based on the UCCSD(T) method with the 6-311+G(3df,2p) basis set. These reactions are important to the propulsion chemistry of the N2O4-N2H3X (X= H, CH3) propellant systems. The results of our calculations show that the hypergolic ignition reactions of NTO with N2H4 and CH3NHNH2, producing N2H3NO + HNO3 and CH3NHN(H)NO...
Source: Computational and Theoretical Chemistry - June 21, 2019 Category: Chemistry Source Type: research

A computational DFT study of methane CH and ammine NH activations by group 9 N-pyrrolyl complexes
Publication date: 15 August 2019Source: Computational and Theoretical Chemistry, Volume 1162Author(s): Bruce M. PrinceAbstractA density functional theory with solvation model density analysis of methane CH and ammine NH activations with Group 9 N-pyrrolyl phosphine complexes (Co, Rh, Ir) is presented. Analysis of the reaction, [{(pyr)3P}M(NH2)]q+, (where M signify Co, Rh, Ir; pyr = N–pyrrolyl and q = +1 and +  for d8 and d6 Group 9) showed that Ir system occurs with a lower free energy barrier. The computed complexes all have reasonable CH activation barriers, ΔG‡ ∼ 18–32 kcal/m...
Source: Computational and Theoretical Chemistry - June 21, 2019 Category: Chemistry Source Type: research

Tuning range-separated DFT functionals for modeling the peak absorption of MEH-PPV polymer in various solvents
In this study, accurate values of ω for three lengths of MEH-PPV polymer (trimer, tetramer, and pentamer) in five different solvents (chloroform, chlorobenzene, xylene, Tetrahydrofuran, and dichloromethane) are reported using the RS functionals wB97XD and CAM-B3LYP. Range separation parameters are predicted and used for longer polymer chains. The differences in the ω for different solvents is statistically significant and gives insight into the polymer/solvent interaction.Graphical abstract (Source: Computational and Theoretical Chemistry)
Source: Computational and Theoretical Chemistry - June 20, 2019 Category: Chemistry Source Type: research

Editorial Board
Publication date: 1 August 2019Source: Computational and Theoretical Chemistry, Volume 1161Author(s): (Source: Computational and Theoretical Chemistry)
Source: Computational and Theoretical Chemistry - June 19, 2019 Category: Chemistry Source Type: research

How much aromatic are naphthalene and graphene?
Publication date: Available online 11 June 2019Source: Computational and Theoretical ChemistryAuthor(s): Vaibhav A. Dixit, Yashita Y. SinghAbstractNaphthalene, polyacenes and graphene are considered aromatic. Existing models for polyacenes predict a linearly increasing aromatic stabilization energy (ASE) and give little insights into their high reactivity and decreasing stability. Graphene’s aromaticity has been studied only qualitatively suggesting alternate Clar’s sextet and two-electrons per ring, and ASE estimates are missing. In this paper, various Enthalpy of Hydrogenation (ΔHhydro) and isodesmic sc...
Source: Computational and Theoretical Chemistry - June 12, 2019 Category: Chemistry Source Type: research

Editorial Board
Publication date: 15 July 2019Source: Computational and Theoretical Chemistry, Volume 1160Author(s): (Source: Computational and Theoretical Chemistry)
Source: Computational and Theoretical Chemistry - June 12, 2019 Category: Chemistry Source Type: research

A Computational DFT Study of Methane C−H and Ammine N−H Activations by Group 9 N-Pyrrolyl Complexes
Publication date: Available online 7 June 2019Source: Computational and Theoretical ChemistryAuthor(s): Bruce M. PrinceAbstractA density functional theory with solvation model density analysis of methane C−H and ammine N−H activations with Group 9 N-pyrrolyl phosphine complexes (Co, Rh, Ir) is presented. Analysis of the reaction, [{(pyr)3P}M(NH2)]q+, (where M signify Co, Rh, Ir; pyr = N−pyrrolyl and q = +1 and +3 for d8 and d6 Group 9) showed that Ir system occurs with a lower free energy barrier. The computed complexes all have reasonable C−H activation barriers, ΔG‡ ∼ 18 to 32 kca...
Source: Computational and Theoretical Chemistry - June 8, 2019 Category: Chemistry Source Type: research

Editorial Board
Publication date: 1 July 2019Source: Computational and Theoretical Chemistry, Volume 1159Author(s): (Source: Computational and Theoretical Chemistry)
Source: Computational and Theoretical Chemistry - June 6, 2019 Category: Chemistry Source Type: research

Modeling and spectral simulation of formic acid dimer in Ar matrix using ONIOM calculations
Publication date: Available online 3 June 2019Source: Computational and Theoretical ChemistryAuthor(s): Fumiyuki ItoAbstractThe supermolecule approach has been used to model molecules embedded in a solid argon matrix. The interaction between the guest and the host atoms in the first solvation shell (FSS) are evaluated using density functional calculations while that beyond the FSS is incorporated using ONIOM calculations to extend the results of our previous study [F. Ito, J. Chem. Phys. 133 (2010) 214502]. The vibrational spectra of a formic acid dimer (FAD) in an Ar matrix was simulated using (FAD)-Arn clusters (n = 94&n...
Source: Computational and Theoretical Chemistry - June 5, 2019 Category: Chemistry Source Type: research

Development of fullerene free acceptors molecules for organic solar cells: A step way forward toward efficient organic solar cells
Publication date: Available online 3 June 2019Source: Computational and Theoretical ChemistryAuthor(s): Muhammad Ans, Khurshid Ayub, Shabbir Muhammad, Javed IqbalAbstractContinuous strides are being made to explore non-fullerene acceptors for organic solar cells. Here, optoelectronic properties of four new acceptor-donor-acceptor (A-D-A) type non-fullerene acceptor molecules are evaluated for their potential use in organic solar cells. The designed molecules contain indacenodithiophene (IDT) donor core connected with various acceptor groups through benzothiadiazole (BT) bridge unit. The designed molecules differ from each ...
Source: Computational and Theoretical Chemistry - June 5, 2019 Category: Chemistry Source Type: research

Quantum molecular dynamic approach to modeling the vibrational spectra of propynenitrile and its 1:1 complexes with water
We present here a quantum molecular dynamic approach from DFT molecular dynamics (DFT/MD) trajectories around 150K, 300K, 450K and 600K to compute the IR spectra of the propynenitrile (or cyanoacetylene) molecule HC3N, the simplest linear cyanopolyyne detected in interstellar clouds and circumstellar envelopes of stars. The DFT/MD results in fair agreement with the experimental data for the isolated molecule are close to those obtained, for all the valence modes, from an effective second order treatment (VPT2) at the CCSD(T) level of theory. This DFT/MD simulation is used to predict the IR spectra of the1:1 complexes with ...
Source: Computational and Theoretical Chemistry - June 3, 2019 Category: Chemistry Source Type: research

Effect of heterocyclic spacer on property of hole-transporting materials with silafluorene core for perovskite solar cells
Publication date: Available online 1 June 2019Source: Computational and Theoretical ChemistryAuthor(s): Zemin Zhang, Rongxing HeAbstractThree hole-transporting molecules S-O, S-S and S-Se are designed through introducing heterocyclic spacers into the silafluorene core of S101. The effects of heterocyclic spacer on the geometry, electronic property and hole mobility of these materials are investigated systematically through using the DFT, Marcus formula and Einstein relation. The HOMO energy levels of S-O, S-S and S-Se are lower than that of S101 from calculated results, indicating that introduction of heterocyclic spacer c...
Source: Computational and Theoretical Chemistry - June 2, 2019 Category: Chemistry Source Type: research

The theoretical study of electronic states with spin-orbit coupling of Zirconium monoxide
Publication date: Available online 1 June 2019Source: Computational and Theoretical ChemistryAuthor(s): J. Tabet, Z. Adem, F. TaherAbstractThe theoretical studies of the electronic structure of ZrO molecule to predict the molecular characteristics and the spectroscopic constants are performed with Ab-initio methods, the (MRCI-SD)/CASSCF. The configuration interaction (CI) method which employed consistent basis sets with effective core potentials for Zr atom, determined 13 singlet and 11 triplet low-lying electronic states below 38600 cm-1. 7 new singlet and 6 new triplet states not yet observed, are calculated for the firs...
Source: Computational and Theoretical Chemistry - June 2, 2019 Category: Chemistry Source Type: research

Introduction of Polar or Nonpolar Groups at the Hydroquinone Units Can Lead to the Destruction of the Columnar Structure of Pillar[5]arenes
Publication date: Available online 31 May 2019Source: Computational and Theoretical ChemistryAuthor(s): Xiao Wang, Rui-xue Chen, Andrew C.-H. Sue, Han Zuilhof, Adelia J.A. Aquino, Hans LischkaAbstractPillar[5]arenes, a type of novel macrocycles containing di-substituted hydroquinone units linked by methylene bridges in para-positions, have attracted extensive attention in supramolecular chemistry as interesting candidates to be used in the preparation of host-guest complexes. Functionalization by means of rim substitution and sustaining an ordered substituent arrangement on both sides of the rim is important for the develo...
Source: Computational and Theoretical Chemistry - June 2, 2019 Category: Chemistry Source Type: research

Analytic treatment of IR-spectroscopy data for double well potential
Publication date: Available online 31 May 2019Source: Computational and Theoretical ChemistryAuthor(s): A.E. SitnitskyAbstractA theoretical scheme for the analysis of experimental data on IR spectroscopy for a quantum particle in a double well potential (DWP) is suggested. The analysis is based on the trigonometric DWP for which the exact analytic solution of the Schrödinger equation is available. The corresponding energy levels along with their wave functions are expressed via special functions implemented in Mathematica (spheroidal function and its spectrum of eigenvalues). As a result trigonometric DWP makes the ca...
Source: Computational and Theoretical Chemistry - June 2, 2019 Category: Chemistry Source Type: research

Excited State Dynamics initiated by an Electromagnetic Field within the Variational Multi-Configurational Gaussian (vMCG) method
Publication date: Available online 30 May 2019Source: Computational and Theoretical ChemistryAuthor(s): T.J. Penfold, M. Pápai, K.B. Møller, G.A. WorthAbstractThe Variational Multi-Configurational Gaussian (vMCG) approach offers a framework to perform exact trajectory-based quantum dynamics. Herein we use two model vibronic coupling Hamiltonians of pyrazine to explore, for the first time, the influence of the coupling between the external field and the Gaussian basis functions (GBFs) in vMCG on the dynamics. We show that when the excitation pulse is short compared to the nuclear dynamics, vertical projection ...
Source: Computational and Theoretical Chemistry - May 31, 2019 Category: Chemistry Source Type: research

Exploring the Electronic Structure and Stability of HgF6: Exact 2-Component (X2C) Relativistic DFT and NEVPT2 Studies
Publication date: Available online 25 May 2019Source: Computational and Theoretical ChemistryAuthor(s): Chun Gao, Shu-Xian Hu, Huixian Han, Guina Guo, Bingbing Suo, Wenli ZouAbstractAs a group 12 element, mercury locating at the sixth row with a valent electronic configuration of 5d106s2 has been treated as a main group element featuring +I and +II oxidation states for a long time. C. K. Jørgensen conjectured the existences of HgF4 and HgF6 molecules in early 1960s, where HgF4 was first synthesized in 2007, but HgF6 as the Hg(+VI) compound was less known. In this paper we explored the electronic structure and decomp...
Source: Computational and Theoretical Chemistry - May 27, 2019 Category: Chemistry Source Type: research

Theoretical study of the reaction mechanism and kinetics of the OH + trimethyl orthoformate ((CH3O)3CH) + O2 reaction
Publication date: 1 July 2019Source: Computational and Theoretical Chemistry, Volume 1159Author(s): Benni Du, Weichao ZhangAbstractThe profiles of potential energy surface (PES) of Trimethyl orthoformate (TMOF) with OH radicals under atmospheric conditions have been studied by performing M06-2X-GD3/6-311++G(d,p) approach for geometry optimization and ab initio method QCISD (T)/6-311++G(d,p) for energy calculations. The reaction of the OH radicals with TMOF in the presence of O2 is found to form mainly OH radicals, 2,2-dimethoxy-1,3-dioxetane, dimethyl carbonate [(CH3O)2CO] and HC(O)H. Regeneration of OH radicals for the TM...
Source: Computational and Theoretical Chemistry - May 25, 2019 Category: Chemistry Source Type: research

On the interaction of propynal with HNO, HF, HCl, H2O, CH3OH, and NH3: Red- and blue-shifting hydrogen bonds and tetrel bonds
Publication date: Available online 22 May 2019Source: Computational and Theoretical ChemistryAuthor(s): Alfred KarpfenAbstractThe potential energy surfaces of the complexes of propynal, (propiolaldehyde, propargyl aldehyde, HCCCOH), with a series of small molecules (HNO, HF, HCl, H2O, CH3OH, and NH3) have been investigated theoretically at the MP2 and CCSD(T) levels using several extended basis sets. Thirty low-lying minima have been detected, eight for HCCCOH-HNO, four for each of the dimers HCCCOH-HF, HCCCOH-HCl, and HCCCOH-H2O, seven for the HCCCOH-CH3OH complex, and three for HCCCOH-NH3. The most stable HCCCOH-HNO comp...
Source: Computational and Theoretical Chemistry - May 24, 2019 Category: Chemistry Source Type: research

Theoretical study of the reaction mechanism and kinetics of the OH + trimethyl orthoformate ((CH3O)3CH)+ O2 reaction
Publication date: Available online 21 May 2019Source: Computational and Theoretical ChemistryAuthor(s): Benni Du, Weichao ZhangAbstractThe profiles of potential energy surface (PES) of Trimethyl orthoformate (TMOF) with OH radicals under atmospheric conditions have been studied by performing M06-2X-GD3/6-311++G(d,p) approach for geometry optimization and ab initio method QCISD (T)/6-311++G(d,p) for energy calculations. The reaction of the OH radicals with TMOF in the presence of O2 is found to form mainly OH radicals, 2, 2-dimethoxy-1, 3-dioxetane, dimethyl carbonate [(CH3O)2CO] and HC(O)H. Regeneration of OH radicals for ...
Source: Computational and Theoretical Chemistry - May 22, 2019 Category: Chemistry Source Type: research

Calculation of the electronic and optical properties of LiFe5O8: An ab initio study
Publication date: Available online 18 May 2019Source: Computational and Theoretical ChemistryAuthor(s): Osmar M. Sousa, Raiane S. Araujo, Sabrina M. FreitasAbstractAb initio calculations based on density functional theory have been employed to study electronic and optical properties of lithium ferrite spinel (LiFe5O8, LFO) based on density functional theory. The calculated of structural properties are in a good agreement with previously reported experimental results. The calculated band gap is indirect with a value of 2.3 eV, which overestimated the experimental value of 1.9 eV. The top of the valence band and the bottom o...
Source: Computational and Theoretical Chemistry - May 20, 2019 Category: Chemistry Source Type: research

Editorial Board
Publication date: 15 June 2019Source: Computational and Theoretical Chemistry, Volume 1158Author(s): (Source: Computational and Theoretical Chemistry)
Source: Computational and Theoretical Chemistry - May 20, 2019 Category: Chemistry Source Type: research

Theoretical studies of capsular complexes of C2V-symmetrical resorcin[4]arene tetraesters with tetramethylammonium cation
Publication date: Available online 17 May 2019Source: Computational and Theoretical ChemistryAuthor(s): Grygoriy Dolgonos, Alexey Tsukanov, Sergey G. Psakhie, Oleg Lukin, Oleksandr Gurbych, Alexander ShivanyukGraphical abstract (Source: Computational and Theoretical Chemistry)
Source: Computational and Theoretical Chemistry - May 18, 2019 Category: Chemistry Source Type: research

A theoretical study of the dication P22+
Publication date: Available online 17 May 2019Source: Computational and Theoretical ChemistryAuthor(s): H. HogreveAbstractEighteen electronic states of the dicationic diphosphorus P22+ and their properties are studied by ab-initio methods. The computed potential energy curves of the ground state 13Σg- and of several other states form local potential wells that are separated from the separated atoms limit by large barriers. The resulting significant lifetimes of numerous vibronic states render the system practically stable against dissociation.Graphical abstract (Source: Computational and Theoretical Chemistry)
Source: Computational and Theoretical Chemistry - May 18, 2019 Category: Chemistry Source Type: research

Th doped carbon clusters ThCn (n = 1–7): Stability and bonding natures
Publication date: 1 July 2019Source: Computational and Theoretical Chemistry, Volume 1159Author(s): Fanrong Yang, Jiguang Du, Gang JiangAbstractThe hybrid HF/DFT functionals in conjunction with small-core pseudopotential have been employed to investigate the geometric and electronic structures of small ThCn (n = 1–7) clusters. The fan-type isomers were found to be more stable than the linear ones. Analyses on the incremental binding energies indicate that the clusters with even C atoms possess the higher stability than odd-numbered ones. The interaction natures of Th-C chemical bonds were revealed by the methods ...
Source: Computational and Theoretical Chemistry - May 16, 2019 Category: Chemistry Source Type: research

Formaldehyde adsorption on a hydrogenated aluminum nitride monolayer: a self-propagated reaction
Publication date: Available online 13 May 2019Source: Computational and Theoretical ChemistryAuthor(s): Alejandro Noguerón, Noé Fernández-Escamilla, Jonathan Guerrero-Sánchez, Noboru TakeuchiAbstractUsing density functional theory calculations, we have studied the functionalization, with formaldehyde, of a hydrogenated hexagonal aluminum nitride (h-AlN) monolayer. The reaction begins with the formaldehyde chemisorption on a hydrogen vacancy of the Al side of the monolayer. This strong interaction is due to the reactive surface dangling bond and it results in a partial breaking of the C=O double ...
Source: Computational and Theoretical Chemistry - May 15, 2019 Category: Chemistry Source Type: research

Th doped carbon clusters ThCn (n=1-7): Stability and bonding natures
Publication date: Available online 10 May 2019Source: Computational and Theoretical ChemistryAuthor(s): Fanrong Yang, Jiguang Du, Gang JiangAbstractThe hybrid HF/DFT functionals in conjunction with small-core pseudopotential have been employed to investigate the geometric and electronic structures of small ThCn (n=1-7) clusters. The fan-type isomers were found to be more stable than the linear ones.Analyses on the incremental binding energies indicate that the clusters with even C atoms possess the higher stability than odd-numbered ones. The interaction natures of Th-C chemical bonds were revealed by the methods of bond o...
Source: Computational and Theoretical Chemistry - May 11, 2019 Category: Chemistry Source Type: research

A Regression Approach to Accurate Interaction Energies Using Topological Descriptors
Publication date: Available online 9 May 2019Source: Computational and Theoretical ChemistryAuthor(s): Francesca Peccati, Eline Desmedt, Julia Contreras-GarcíaAbstractMachine learning has a wide range of applications in chemistry, encompassing the prediction of the structure and properties of a variety of chemical systems (molecules, macromolecules and solids). The idea of using a self-learning algorithm to explore chemical problems is particularly alluring when facing open challenges in theoretical chemistry, such as non-covalent interactions, which are known to be critical for density functional methods. Additiona...
Source: Computational and Theoretical Chemistry - May 10, 2019 Category: Chemistry Source Type: research

Trace benzene removal from vinyl acetate with ZIFs: A computational study
Publication date: Available online 8 May 2019Source: Computational and Theoretical ChemistryAuthor(s): Dong Xiuqin, Chen Shumin, Chen Yifei, Zhang MinhuaAbstractThe removal of trace benzene from vinyl acetate with zeolitic imidazolate frameworks (ZIFs), a kind of metal-organic frameworks (MOFs) with formula unit M(IM)2 is studied. ZIF-2, ZIF-3, ZIF-6, ZIF-8, ZIF-10, and ZIF-68 are selected to study the adsorption of benzene and vinyl acetate. Density functional theory (DFT) method is used to study the interaction of the adsorbed molecules with the metal and organic linkers of ZIFs. Various adsorption positions are examined...
Source: Computational and Theoretical Chemistry - May 8, 2019 Category: Chemistry Source Type: research

The mechanism and kinetics of the gas-phase reactions of OH radicals with O,O-diethyl methylphosphonothioate, (C2H5O)2P(S)CH3: theoretical investigations
Publication date: Available online 3 May 2019Source: Computational and Theoretical ChemistryAuthor(s): Vahid SahebAbstractIn this research, the kinetics of bimolecular reaction of O,O-diethyl methylphosphonothioate (DEMPT) with OH radical is investigated theoretically. First, the mechanism of the reaction of OH radical with DEMPT is explored some well-tested density functional methods. Next, the constants for different reaction pathways are calculated by statistical rate theories. The results are compared with available experimental data. The present calculations reveal that in the most favorable reaction pathway, the reac...
Source: Computational and Theoretical Chemistry - May 4, 2019 Category: Chemistry Source Type: research

Theoretical study on the efficacy of DBN/LiBr system as a catalyst for fixation of CO2 with propylene oxide: solvent effects on activation barriers
Publication date: Available online 30 April 2019Source: Computational and Theoretical ChemistryAuthor(s): Teshome Abute LelishoGraphical abstract (Source: Computational and Theoretical Chemistry)
Source: Computational and Theoretical Chemistry - May 1, 2019 Category: Chemistry Source Type: research

Electronic states, spectroscopic parameters, transition probabilities, and radiative lifetimes of the scandium monosulfide cation, ScS+: A theoretical contribution
Publication date: Available online 30 April 2019Source: Computational and Theoretical ChemistryAuthor(s): João Gabriel Farias Romeu, Fernando R. OrnellasAbstractHigh-level CASSCF/MRCI calculations with cc-pV5Z basis sets were employed to characterize a manifold of electronic states of the monosulfide cation ScS+ correlating with the three-lowest dissociation channels. The global energetic picture provided by the potential energy curves makes evident a region, especially above 35000 cm-1, of high density of electronic states that presents a challenge for both experimentalists and computational chemists to assign prop...
Source: Computational and Theoretical Chemistry - May 1, 2019 Category: Chemistry Source Type: research

Editorial Board
Publication date: 1 June 2019Source: Computational and Theoretical Chemistry, Volume 1157Author(s): (Source: Computational and Theoretical Chemistry)
Source: Computational and Theoretical Chemistry - April 28, 2019 Category: Chemistry Source Type: research

Mechanistic insights into silver(I)-mediated trifluoromethylation of aryldiazonium salts
Publication date: Available online 25 April 2019Source: Computational and Theoretical ChemistryAuthor(s): Xiang ZhangAbstractThe mechanism of silver(I)-mediated trifluoromethylation of aryldiazonium salts has been studied comprehensively with density functional theory (DFT). Three stages constitute the trifluoromethylation pathway, namely i) dissociation of the aryldiazonium salt, ii) formation of the key disilver(I) intermediate and iii) disilver(I)-mediated oxidative addition/reductive elimination (OA/RE) reaction. Thereinto, oxidative addition is the rate-determining step in the whole reaction. A radical pathway can be ...
Source: Computational and Theoretical Chemistry - April 25, 2019 Category: Chemistry Source Type: research

Comparison of mono- and di-substituted triphenylamine and carbazole based sensitizers @(TiO2)38 cluster for dye-sensitized solar cells applications
This study has been performed to understand the effect of donor strength on photovoltaic performance of Dye-sensitized Solar Cells (DSSCs). For this purpose, Density Functional Theory (DFT) and time domain DFT calculations were carried out. The results reveal that triphenylamine based Dye 2 and carbazole based Dye 4 with di-substituted donor moieties showed red shifted absorption wavelengths, higher oscillator strength and improved electron injection leading to the larger short-circuit photocurrent density (JSC). It is expected that these dyes might show larger open-circuit photovoltage (VOC) as well. These results disclos...
Source: Computational and Theoretical Chemistry - April 25, 2019 Category: Chemistry Source Type: research

Structural, electronic and energetic effects in heterocyclic fluorene derivatives fused with a fulvene unit
Publication date: Available online 22 April 2019Source: Computational and Theoretical ChemistryAuthor(s): Małgorzata Leszczyńska, Krzysztof EjsmontAbstractA set of 36 heterocyclic (B, N and O) fluorene (C) derivatives fused in nine ways with fulvene ring have been analyzed by means of different local aromaticity criteria. Molecular geometry of analyzed compounds were optimized at B3LYP/6-311++G(2d,2p) level of theory. The evaluation of the local aromaticity has been carried out through the use of the geometry-based harmonic oscillator model of aromaticity (HOMA) and the magnetism-based zz‐component of the nucleus indep...
Source: Computational and Theoretical Chemistry - April 23, 2019 Category: Chemistry Source Type: research