The effect of substitution on boron in the Diels-Alder reactions of vinylboranes has been investigated by a computational study performed with the B3LYP/6-31G* method. Four vinylboranes with different electronic and steric properties were chosen to study the reactivity and the regioand stereoselectivities patterns. In general, the calculations for the reactions with cyclopentadiene, trans-piper...

Abstract Cumulenes and polyynes have the potential to be applied as linear, sp -hybridized, one-dimensional all-carbon nanowires in molecular electronics optoelectronics. The delocalization conductivity descriptors of two ?-conjugated systems, heterodisubstituted with NO 2 , CN, NH OH groups, were studied using B3LYP, B3LYP/D3, CAM-B3LYP, ?B97XD DFT functionals, combined aug-cc-pVTZ basis set. ...

Abstract In the present study, 3- p -methoxybenzyl/ m -chlorobenzyl/phenyl-4-(3-methyl-2-thienylmethyleneamino)-4,5-dihydro-1 H -1,2,4-triazol-5-ones were obtained from reaction between 3-methylthiophene-2-carbaldehyde and three different 4-amino-(3- -chlorobenzyl/phenyl)-4,5-dihydro-1 -1,2,4-triazole-5-ones. order to compare experimental theoretical values, geometric parameter, electronic, non...

Quinolines are aromatic compounds consisting of benzene rings with a pyridine heterocyclic system. In this study, the structure and orbital interactions methyl 5-6 dihydro benzo(h) quinolone-4-carboxylate (MDQC) molecule, which is quinoline derivative, were analyzed. calculation using B3LYP/6-311++g(d,p) level, three conformers found in minimum energy state according to O=C-O-C dihedral angle s...

Using a set of oscillator strengths and excited-state dipole moments near full configuration interaction (FCI) quality determined for small compounds, we benchmark the performances several single-reference wave function methods (CC2, CCSD, CC3, CCSDT, ADC(2), ADC(3/2)) time-dependent density-functional theory (TD-DFT) with various functionals (B3LYP, PBE0, M06-2X, CAM-B3LYP, $\omega$B97X-D). We...

This paper deals with the evaluation of lipophilicity expressed by logPow parameter ten barbiturate derivatives generally used as sedative-hypnotics based on Density Functional Theory (DFT) calculations. All geometry optimizations and frequency calculations have been carried out using DFT/B3LYP/ 6-311++G (d,p) basis set in gas phase also water n-octanol phases. Gibbs free energies solvation for...

The infrared (IR) and Raman spectra of triphenylene with intensities were calculated using both density functional theory (DFT, B3LYP method) and Moller-Plesset perturbation method of second order (MP2) with ccpVDZ basis set. Spectra were compared with experimentally measured; the agreement between the observed and calculated spectra is good in case of IR spectroscopy, MP2 simulated spectra wer...

Previously, we have put forward the X1 method that combines B3LYP with neural network correction for an accurate yet efficient prediction of thermochemistry. Without paying additional computational cost, X1 reduces B3LYP's mean absolute deviation (MAD) for a set of 92 bond dissociation energies (BDEs) from 5.5 to 2.4 kcal mol(-1). In this work, we extend X1 and propose the X1s method by includi...

Theoretical calculations have been performed for different possible hydrogen bonding complexes between adenine and hydrogen peroxide (AHP). The studied complexes (1-6) were cyclic ones showing two hydrogen bonds of different strength. All of the structures have been characterized at the B3LYP/6-31G(2d,p) and MP2(full)/6-31G(2d,p) levels, yielding only real frequencies (minima) at the B3LYP/6-31...

In this research, Quantum-mechanical calculations were performed at the HF method with the 6-31+G*basis set and at the B3LYP method with the 6-31+G* basis set in the gas phase and five solvents such as water, DMSO, methanol, ethanol and dichloromethane at six temperatures. According to these theoretical results of IR, we extracted thermo chemical parameters such as enthalpy (∆H Kcal/mol), Gibbs...