title: Vibrational spectra and natural bond orbital analysis of the herbicidal molecule 2(4-chlorophenoxy)-2-methyl propionic acid.
abstract: The herbicide 2(4-chlorophenoxy)-2-methyl propionic acid (MCPP) has been subjected to NIR FT-Raman and infrared spectral studies. The optimized molecular structure, vibrational wavenumbers, IR intensities and Raman activities have been calculated by using density functional method (B3LYP) with the standard 6-31G(d) basis set. The calculated molecular geometry has been compared with the XRD data. The detailed assignments of the normal modes have been performed based on the potential energy distribution (PED) following the scaled quantum mechanical force field (SQMFF) methodology. The IR and Raman spectra have been plotted for the calculated wavenumbers. The simulated spectra satisfactorily coincide with the experimental spectra. The strong hyperconjugative interaction and charge delocalization that leads to the stability of the molecule have been investigated with the aid of natural bond orbital (NBO) analysis.
authors.affiliation: Department of Physics, Scott Christian College (Autonomous), Nagercoil 629003, TamilNadu, India.
authors.forename: J Clemy
authors.initials: JC
authors.lastname: Monicka
authors.forename: C
authors.initials: C
authors.lastname: James
mesh_terms: D002264:Carboxylic Acids / Q000737:chemistry; D002995:Clofibric Acid / Q000737:chemistry*; D006540:Herbicides / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D010636:Phenols / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D014732:Vibration; D014961:X-Ray Diffraction
chemical_list: D002264:Carboxylic Acids; D006540:Herbicides; D010636:Phenols; D002995:Clofibric Acid