title: Molecular structure of phenyl- and phenoxyacetic acids--spectroscopic and theoretical study.
abstract: The FT-IR, FT-Raman and (1)H and (13)C NMR spectra were recorded for phenyl- and phenoxyacetic acids in comparison with benzoic acid molecule. The density functional hybrid method (B3LYP/6-311++G(**)) was used to calculate optimized geometrical structures of studied compounds. The atomic charges were calculated by NBO (natural bond orbital) methods. Aromaticity indices, dipole moments and energies as well as the wavenumbers and intensities of IR spectra were calculated. The chemical shifts in NMR spectra using the gauge independent atomic orbital (GIAO) method were also analyzed. The theoretical parameters were compared to experimental characteristic of phenyl- and phenoxyacetic acids. The study of HOMO, LUMO and NBO analyses have been used to elucidate charge transfer within the molecule of title compounds. Molecular electrostatic potential (MEP) was also calculated.
authors.affiliation: Division of Chemistry, Bialystok University of Technology, 15-435 Białystok, Zamenhofa 29, Poland. Electronic address: m.samsonowicz@pb.edu.pl.
authors.forename: M
authors.initials: M
authors.lastname: Samsonowicz
mesh_terms: D000085:Acetates / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D055672:Static Electricity
chemical_list: D000085:Acetates; C415326:phenoxyacetic acid
keywords: DFT calculations; HOMO/LUMO analysis; IR; Molecular electrostatic potential; NMR; Raman