title: DFT computation and experimental analysis of vibrational and electronic spectra of phenoxy acetic acid herbicides.
abstract: An absolute vibrational analysis has been attempted on the basis of experimental FTIR and NIR-FT Raman spectra with calculated vibrational wavenumbers and intensities of phenoxy acetic acids. The equilibrium geometry, bonding features and harmonic vibrational wavenumbers have been calculated with the help of B3LYP method with Dunning correlation consistent basis set aug-cc-pVTZ. The electronic structures of molecular fragments were described in terms of natural bond orbital analysis, which shows intermolecular O-H···O and intramolecular C-H···O hydrogen bonds. The electronic absorption spectra with different solvents have been investigated in combination with time-dependent density functional theory calculation. The pKa values of phenoxy acetic acids were compared.
authors: Department of Physics, Nesamony Memorial Christian College, Marthandam 629 165, Tamil Nadu, India.
authors: D
authors: D
authors: Arul Dhas
authors: I
authors: I
authors: Hubert Joe
authors: S D D
authors: SD
authors: Roy
authors: S
authors: S
authors: Balachandran
mesh_terms: D000085:Acetates / Q000737:chemistry*; D004583:Electrons; D006540:Herbicides / Q000737:chemistry*; D006860:Hydrogen Bonding; D008958:Models, Molecular; D008968:Molecular Conformation; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D055672:Static Electricity; D014732:Vibration; D014961:X-Ray Diffraction
chemical_list: D000085:Acetates; D006540:Herbicides; C415326:phenoxyacetic acid