title: Density functional theory, comparative vibrational spectroscopic studies, NBO, HOMO-LUMO analyses and thermodynamic functions of N-(bromomethyl)phthalimide and N-(chloromethyl)phthalimide.
abstract: Quantum mechanical calculations of energies, geometries, and vibrational wavenumbers of N-(bromomethyl)phthalimide and N-(chloromethyl)phthalimide are carried out using density functional theory (DFT/B3LYP) method with 6-31G and 6-311G(d,p) basis sets. The optimized geometrical parameters obtained by B3LYP method show good agreement with experimental data. The difference between the observed and scaled wavenumber values of most of the fundamentals is very small. A detailed interpretation of the infrared and Raman spectra of N-(bromomethyl)phthalimide and N-(chloromethyl)phthalimide was also reported. The calculated HOMO and LUMO energies show that charge transfer occurs in the molecules. The thermodynamic functions of N-(bromomethyl)phthalimide and N-(chloromethyl)phthalimide have been performed at B3LYP/6-31G and B3LYP/6-311G(d,p) basis sets. The theoretical spectrograms for FT-IR and FT-Raman spectra of N-(bromomethyl)phthalimide and N-(chloromethyl)phthalimide have also been constructed.
authors.affiliation: Research Department of Physics, A A Government Arts College, Musiri 621 211, India. brsbala@rediffmail.com
authors.forename: V
authors.initials: V
authors.lastname: Balachandran
authors.forename: S
authors.initials: S
authors.lastname: Lalitha
authors.forename: S
authors.initials: S
authors.lastname: Rajeswari
mesh_terms: D054879:Halogenation; D008745:Methylation; D008958:Models, Molecular; D008968:Molecular Conformation; D010797:Phthalimides / Q000737:chemistry*; D011789:Quantum Theory; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D013816:Thermodynamics
chemical_list: D010797:Phthalimides