@Article{, title={Theoretical study of frequencies modes, energy gap and HOMO –LUMO energies in solvents combinations for monomer urea}, author={Wisam A.Radhi}, journal={Muthanna Journal of Pure Science (MJPS) مجلة المثنى للعلوم الصرفة}, volume={1}, number={1}, pages={278-290}, year={2013}, abstract={Molecular structure determination for monomer urea as well as theirvibrational frequencies have been theoretically investigated by molecular orbitalby Ab Initio calculation based on DFT theory level using 6-311G basis setperformed by B3LYP method. Assignments for vibrational frequencies weremade, and solvent effect on the IR frequencies using eleven solvents: water,Dimethylsulfoxied, Ethanol, Acetone, Aniline, Chlorobenzene, Chloroform,Toluene, Benzene ,Cyclohexane and Heptane. The vibration mode of carbonylis shifted to lower frequencies while the NH2 bending increased in polar solvent.The correlation between the dielectric constant and parameters[C=O freq.,Energy gap, HOMO and LUMO] in eleven solvents obtained values r2 withrange 0.890-0.973

} }