In this research at the first 2-amino-3-(3,4-dihydroxyphenyl)-2-methyl-propanoic acid  drug and its fullerene derivative were optimized. NMR calculations for the complexes were carried out at the B3LYP/6-31G*quantum chemistry level. Different parameters such as energy levels, the amount of Chemical Shift in different atoms, the amount of HOMO/LUMO, chemical potential (µ ), chemical hardness (η)...

Theoretical modeling of chemical and biological processes is a key to understand nature and to predict experiments. Unfortunately, this is very data and computation extensive. However, the worldwide computing grid can now provide the necessary resources. Here, we present a coupling of the GAMESS quantum chemical code to the Nimrod/G grid distribution tool, which is applied to the parameter scan...

The aqueous speciation of selenium(iv) was elucidated by a combined approach applying quantum chemical calculations, infrared (IR), Raman, and (77)Se NMR spectroscopy. The dimerization of hydrogen selenite (HSeO3(-)) was confirmed at concentrations above 10 mmol L(-1) by both IR and NMR spectroscopy. Quantum chemical calculations provided the assignment of vibrational bands observed to specific...

For studying both hydrogen bond and dipole-dipole interactions between methanol molecules (self-association) the geometry of clusters of increasing numbers of methanol molecules (n = 1,2,3) were optimized and also their vibrational frequencies were calculated with quantum chemical methods. Beside these B3LYP/6-311G** calculations, PCM calculations were also done for all systems with PCM at the ...

Over the past decade, the chemical behavior of flavonoids as antioxidants has become the subject ofintense experimental research. Plants represent a main source of natural antioxidants that might serveas leads for the development of novel drugs. Malva sylvestris L. known to have various medicinalproperties since several decade ago, were evaluated for their antioxidant compounds ,Most of thesebi...

A new ab initio approach to the calculation of X-ray spectra is demonstrated. It combines a high-level quantum chemical description of the chemical interactions and local atomic multiplet effects. We show here calculated L-edge X-ray absorption (XA) and resonant inelastic X-ray scattering spectra for aqueous Ni(2+) and XA spectra for a polypyridyl iron complex. Our quantum chemical calculations...

in this research, the effect of the first order magnetic field on the ground-state of a centered hydrogenic donor impurity in a gaas/alas spherical quantum dot has been calculated. the perturbation method has been used within the framework of effective mass approximation for these calculations. overall, the analysis shows that a proper choice of quantum dot radius and magnetic field can signifi...