Partial atomic charges provide an intuitive and efficient way to describe the charge distribution resulting intermolecular electrostatic interactions in liquid water. Many models exist it is unclear which model provides best assignment of partial response local molecular environment. In this work, we systematically scrutinize various electronic structure methods (Mulliken, natural population an...

Quantum transport properties of pure and functioned infinite lead-connection region-lead systembased on the zigzag graphene nanoribbon (2-zGNR) have been investigated. In this work the effectof the doping functionalization on the quantum transport of the 2-zGNR has been computationallystudied. Also, the effect of the imposed gate voltages (-3.0, 0.0 and +3.0 V) and bias voltages 0.0 to2.0 V hav...

phospholipids are important for the biological lipid and are commonly used in biophysical studies.a quantumcalculation for two phospholipids dipalmitoylphosphatidylethanolamine and dipalmitoylphosphatidic acidwere performed using the abinitio software. geometry optimization structures were obtained at rhf level using3-21g, 6-31g*. these basis sets were used to understanding the effects of envir...

Potassium Alanate is one of the goal candidates for hydrogen storage during past decades. In this report, initially the Density Functional Theory was applied to simulate the electronic and structural characteristic of the experimentally known KAlH4 complex hydride. The relaxation of unit cell parameters and atomic positions was performed until the total residual force reduced less than 0.001ev ...

Accurate electron densities and X-ray form factors of Li, Be, F and their ions have been calculated. Electron correlation, crystal fields and ionic charge transfer change the form factors by up to a few percent, mainly in the range of sin 0 /k < | Ä " 1 . Although electron correlation and crystal fields are small perturbations, their effects on the density and form factor are not additive. Dens...

Electron crystallography has the potential to analyze crystals of membrane proteins and macromolecular complexes too small or too thin for X-ray crystallography, as electrons are scattered 4 5 orders of magnitude more strongly than X-rays. Electron crystallography yields Coulomb potential maps, rather than electron density maps as X-rays do, providing information on charged states of amino-acid...

Molecular modelling is routinely employed to assign 3D structures to collision cross sections (CCSs) derived from ion mobility mass spectrometry experiments (IM-MS). The assignment of model structures to the experimental CCSs remains an ambiguous task, where one of several methods may be used to obtain a CCS from a given set of coordinates. The most reliable of the commonly used techniques, the...

Current researches have showed that N3, N5-diaryl-2, 6-dimethyl -1, 4-dihydropyrine-3, 5- dicarboxamide analogues demonstrate notable anti-tubercular activity. In this study, Hantzsch condensation was used to design and synthesize new analogues of dihydropyridine (DHP). Different diary carboxamides were inserted at positions 3 and 5 of the DHP ring. 4(5)-chloro-2-ethyl-5(4)-imidazolyl moiety wa...