The Dopamine has been studied theoretically at the B3LYP/6-31G* level were performed in gasphase. We calculated physical parameters like atomic charges, energy (=>), asymmetry parameter(?), chemical shift @iso, dipole moment and isotropic NMR determinant and in this work we usedGaussian 03 at NMR and calculation by using B3LYP methods with 6-31G* basis set.

Symmetrical and non-symmetrical diimines derived from dimedone were synthesized by the reaction of their corresponding enaminothiones with primary amines. The synthesized compounds were characterized using micro analytical data and NMR spectroscopy. Theoretical calculations by B3LYP/6-31G(d,p) level of theory show that the enolic form is the most stable within the possible tautomeric forms of t...

IR and Raman spectra of 2,6-dimethoxyphenol were recorded and analyzed. The vibrational wavenumbers of the compound have been computed using the Hartree-Fock/6-31G* basis and compared with the experimental values. Predicted infrared intensities and Raman activities are reported.

The total number of possible retrosynthetic bisections of C(60) leads to nine different isometric C(30) fragments. These molecules include five chiral units, four of which derive from partitions corresponding to four distinct "Coupes du Roi". The energies, curvatures, and homodesmotic stabilization energies of the C(30) fragments are evaluated at the ab initio 6-31G level.

The conformational space of C a-L-fucose was searched by the MM2*-SUMM 4 molecular mechanics conformational search technique. The molecular geometries of the first 17 structures of lowest energy were analyzed at the HFr3]21G, Ž . Ž . 6]31G d , and generalized gradient approximation GGA DFT levels of theory. Q 1997 by John Wiley & Sons, Inc.

The relative energies of the chair and boat transition states of a variety of Ireland-Claisen rearrangements were obtained by B3LYP/6-31G calculations. Theoretical results are in good agreement with experimental data and provide a quantitative analysis of the origins of boat preferences that are observed in some of these reactions.

Fulvene is a non-aromatic molecule, but variation of the electron-donating/withdrawing power of substituents exo to the five-membered ring can drive the system between the extremes of aromatic and antiaromatic, as judged by prediction of fully developed diatropic and paratropic ring currents through ab initio calculations made at the ipsocentric 6-31G**/CTOCD-DZ CHF level.

The clustering energies and geometries of the H2CN • MN2 (w = 1, 2 and 3) species have been determined by ab initio SCF calculations with the 4-31G basis set. The calculated clustering energies are in good agreement with the experimentally estimated heats of formation of the corresponding clusters. The stability of various conformers has been studied in terms of localized orbitals and charge di...

polycyclic aromatic hydrocarbons (pahs) are a class of compounds consisting of more than twobenzene rings fused in a linear, angular, or clustered arrangement and do not contain hetero atomsor carry subsistent. pahs originate from various sources. they are primarily formed byincomplete combustion of carbon-containing fuels such as wood, coal, diesel, fat, or tobacco. thepresent study reports an...

in this paper, the structural properties of the b30n20 molecule have been investigated at b3lyp/6-31g (d) level of theory. the optimized structure and electronic properties calculations for the studiedmolecule have been performed using gaussian 03 program. a mathematical equation of third degreewas exploited for the correlation and exchange energy with the number of primitives. the naturalbondi...