in the present work, an extensive theoretical calculation study on histidine-histidine dipeptide in gas phase is done by using dft method with gaussian 98 program. through investigations on the molecular geometries of this molecule it is found that there is six rings in the molecules not two rings. the presence of four intramolecular hydrogen bonds is responsible for the formation of additional...

In the present work, an extensive theoretical calculation study on Histidine-Histidine dipeptide in gas phase is done by using DFT method with Gaussian 98 program. Through investigations on the molecular geometries of this molecule it is found that there is six rings in the molecules not two rings. The presence of four intramolecular hydrogen bonds is responsible for the formation of additional...

Equilibrium geometry, electronic structures, and vibrational modes of CoB8- were investigated in the PBEPBE/6-311+G(d,p) level of theory. The nucleus independent chemical shift (NICS) analysis and magnetizability values were used for studying of aromaticity in CoB8-. The effects of different solvents on the structure and frontier orbital energies were calculated using the polarizable continuum ...

equilibrium geometry, electronic structures, and vibrational modes of cob8- were investigated in the pbepbe/6-311+g(d,p) level of theory. the nucleus independent chemical shift (nics) analysis and magnetizability values were used for studying of aromaticity in cob8-. the effects of different solvents on the structure and frontier orbital energies were calculated using the polarizable continuum ...

h6-benzne, h6-garphyne) was studied with MPW1PW91 quantum chemical computations. Quantumtheory of atoms in molecules (QTAIM) was applied to elucidate these complexes Cr-CO bonds. Theellipticity (e) and h values of the Cr-CO bonds were calculated. The amount of pp-dp back-donation ofCr-CO bonds were illustrated by calculation of the magnitude of the quadrupole polarization of c...

It seems that the general applicability of the quantum theory of atoms in molecules (QTAIM) oncharacterizing the bonded interactions is still questionable even afier 30 years since its formulation. Fordemonstrating the generality of bonding schemes in QTA IM, ea( isomers were chosen as the modelsystems and the results from molecular charge density analysis and vibrational normal modes werecompa...

Topological analysis has been performed on the total electron density of the two forms of Ozonemolecule,C2V and D3H ,to investigate the nature of chemical bonds ,molecular structure , atomiccharges and electrical properties. While these concepts have been completely discussed usingclassical models the emphasize in this work is based on Quantum Theory of Atoms in Molecules(QTAIM). Because the D3...

it seems that the general applicability of the quantum theory of atoms in molecules (qtaim) oncharacterizing the bonded interactions is still questionable even afier 30 years since its formulation. fordemonstrating the generality of bonding schemes in qta im, ea( isomers were chosen as the modelsystems and the results from molecular charge density analysis and vibrational normal modes werecompa...