title: Conformational stability, spectroscopic (FT-IR, FT-Raman and UV-Vis) analysis, NLO, NBO, FMO and Fukui function analysis of 4-hexylacetophenone by density functional theory.
abstract: The experimental and theoretical study on the structures and vibrations of 4-hexylacetophenone (abbreviated as 4HAP) are presented. The FT-IR and FT-Raman spectra of the title compound have been recorded in the region 4000-400cm(-1) and 3500-100cm(-1) respectively. The molecular structures, vibrational wavenumbers, infrared intensities and Raman activities were calculated using DFT (B3LYP and LSDA) method with 6-311++G(d,p) basis set. The most stable conformer of 4HAP is identified from the computational results. The assignments of the vibrational spectra have been carried out with the aid of normal coordinate analysis (NCA) following the scaled quantum mechanical force field methodology (SQMEF). The linear polarizability (α) and the first hyperpolarizability (βtot) values of the investigated molecule have been computed using B3LYP and LSDA with 6-311++G(d,p) basis set. Stability of the molecule arising from hyper conjugative interaction and charge transfer delocalization has been analyzed using natural bond orbital (NBO) analysis. The molecule orbital contributions are studied by density of energy states (DOSs). UV-Vis spectrum and effects of solvents have been discussed effects of solvents have been discussed and the electronic properties such as HOMO and LUMO energies were determined by time-dependent TD-DFT approach. Fukui function and Mulliken analysis on atomic charges of the title compound have been calculated. Finally, electrophilic and nucleophilic descriptors of the title molecule have been calculated.
authors.affiliation: Department of Physics, Karpagam University, Coimbatore 641 021, India; Department of Physics, J.J. College of Arts and Science (Autonomous), Pudukkottai 622 422, India.
authors.forename: S
authors.initials: S
authors.lastname: Saravanan
authors.affiliation: Centre for Research, Department of Physics, AA Government Arts College, Musiri, Tiruchirappalli 621 211, India. Electronic address: brsbala@rediffmail.com.
authors.forename: V
authors.initials: V
authors.lastname: Balachandran
mesh_terms: D000098:Acetophenones / Q000032:analysis* / Q000737:chemistry; D000465:Algorithms; D006860:Hydrogen Bonding; D008958:Models, Molecular; D008968:Molecular Conformation; D015394:Molecular Structure; D055095:Optics and Photonics; D011427:Propiophenones / Q000032:analysis* / Q000737:chemistry; D011789:Quantum Theory; D012984:Software; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D014961:X-Ray Diffraction
chemical_list: C000603911:4-hexylacetophenone; D000098:Acetophenones; D011427:Propiophenones
keywords: DFT calculations; Fukui function; Hyperpolarizability; PES scan; Vibrational analysis; Vibrational spectra