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. ...

Quantum mechanical calculations of energies, geometries and vibrational wavenumbers of 2-fluoro-5-methylbenzonitrile (2F5MBN) have been carried out by using density functional theory (DFT/B3LYP) method with 6-311++G(d,p), cc-pvdz, Aug-cc-pvdz as basis sets. The optimized geometrical parameters obtained by DFT calculations are found to be in good agreement with experimental X-ray data. The best ...

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...

Abstract Optical spectroscopy (UV-vis and fluorescence spectroscopy) is sensitive to the chemical environment conformation of fluorophores therefore, serves as an ideal probe for solvent responses. Tyrosine kinase inhibitors (TKI) such AG-1478 epidermal growth factor receptor (EGFR) when containing a quinazolinamine scaffold are fluorophores. It is, however, very important benchmark density fun...

Geometry optimizations of all cluster models were carried out in solution with Integral Equation Formalism Polarizable Continuum Model (IEFPCM) as implemented in Gaussian09. The B3LYP functional in conjunction with the 6-31+g(d) basis set was employed to optimize the geometries. Frequency calculations at the same level of theory were carried out to verify the nature of the stationary points enc...

We perform a systematic examination on the dependence of the calculated nuclear magnetic shielding constants on the chosen geometry for a selective set of density functional methods of B3LYP, PBE0, and OPBE. We find that the OPBE exchange-correlation functional performs remarkably well when either the optimized geometries or the experimental geometries are used. The popular B3LYP and PBE0 funct...

Electronic circular dichroism (ECD) parameters of the disulphide chromophore have been calculated for dihydrogen disulphide, dimethyl disulphide, and cystine using density-functional theory, coupled-cluster theory, and multiconfigurational self-consistent field theory. The objective is twofold: first, to examine the performance of the Coulomb-attenuated CAM-B3LYP functional for the calculation ...

Fourier transform Raman and infrared spectra of 4-hydroxy-2,6-dimethyl pyrimidine (HDMP) were recorded and interpreted by comparison with respective theoretical spectra calculated using HF and B3LYP methods. The HDMP equilibrium geometry with Cs symmetry, harmonic vibrational frequencies, infrared and Raman intensities were determined using HF/6-311G and B3LYP/6-311G level of theories. The band...