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. Computational details Our calculations are based on the implementation of plane wave density functional theory (DFT) in the Kohn–Sham framework using ABINIT simulation package. 1 The Abinit code is a common project of the University Catholique de Louvain

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density approximation of the density functional theory (DFT). The thermodynamical properties have been calculated using density functional perturbation theory (DFPT). Differences in the ground state, electronic and thermodynamic properties of GaP and Ga 2

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article, we report a systematic study on the pressure dependence of the phonon spectra and thermal properties of two transition metal nitrides using first principle calculations under the frame work of density functional theory (DFT

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Computational chemistry Density functional theory (DFT) calculations were carried out using the Amsterdam density functional (ADF) 2009 programme [ 27 – 29 ] with the generalized gradient approximation functional PW91 (Perdew–Wang, 1991) [ 30 ]. The

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summary, we have investigated the phase transition of TiN from the NaCl structure to the CsCl structure by the ab initio plane-wave pseudopotential density functional theory method. The pressure of transition from the NaCl structure to the CsCl structure

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isolated and deposited on a carbon support. The interaction between H 2 and the dimers is investigated by means of a simple theoretical approach based on density functional theory (DFT) combined with relatively modest basis sets. Our work addresses the

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Abstract  

Theoretical calculations based on the density functional theory (DFT) were performed to understand the effect of substituents on the molecular and electronic structures of technetium nitrido complexes with salen type Schiff base ligands. Optimized structures of these complexes are square pyramidal. The electron density on a Tc atom of the complex with electron withdrawing substituents is lower than that of the complex with electron donating substituents. The HOMO energy is lower in the complex with electron withdrawing substituents than that in the complex with electron donating substituents. The charge on Tc atoms is a good measure that reflects the redox potential of [TcN(L)] complex.

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Ziegler-Natta catalytic systems

Calorimetric and DFT study on TiCl4-Lewis base interactions

Journal of Thermal Analysis and Calorimetry
Authors: L. Cavallo, J. Ducéré, Rosalisa Fedele, A. Melchior, Maria Mimmi, G. Morini, F. Piemontesi, and Marilena Tolazzi

Abstract  

A calorimetric investigation on the reactions of TiCl4 with phthalates in 1,1,2,2-tetrachloroethane (TCE) is presented in order to better understand the complex interactions present in Ziegler-Natta catalytic systems. The Lewis bases diethyl isophthalate (L1), diethyl terephthalate (L2) and the ortho-isomer diethylphthalate (L3), have been chosen to study how the substituent positions could influence the energy and the stoichiometry of the complexation reactions. FTIR spectroscopy was used to obtain information on the coordination mode of the ligands and diffusion measurements by NMR was carried out to verify the presence of oligo-or polymeric species. Experimental results were compared with theoretical calculations based on Density Functional Theory (DFT).

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The results of first principles calculations of band structure, density of states and electron density topology of CdC2O4 and Ag2C2O4 crystals are presented. The calculations have been performed with WIEN2k ab initio program, using highly precise full potential linearized augmented plane wave (FP LAPW) method within Density Functional Theory formalism. The obtained SCF electron density has been used in calculations of Bader’s AIM (atoms in molecules) topological properties of the electron density in crystal. The obtained results show important similarities in electronic structure and electron density topology of both compounds and allow supposing, that during the thermal decomposition process these compounds should behave similarly, which is in agreement with the experiment.

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We report the theoretical analysis results of thermochemical properties of solvated Li+ ion in propylene carbonate (PC), which is one of the most popular solvents used in the lithium-ion battery composite. In the theoretical calculation, we employed the density functional theory method with the 6-31G basis set using the Gaussian03 package. It has been made clear that the solvation with four PC molecules around a Li+ ion is most favorable. Detailed results of the conventional quantum chemical analyses for these materials will also be presented. Thermochemical properties such as the standard (that is at 298.15 K and 101325 Pa) enthalpy, entropy, and Gibbs energy changes upon the formation of Li+ complexes solvated with PC molecules have been numerated and discussed. Furthermore, we will afford the features of desolvation of the solvated Li+ ion complexes when they interact with the carbon electrode modeled by ovalene molecules.

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