title: The spectroscopic (FT-IR, FT-Raman), MESP, first order hyperpolarizability, NBO analysis, HOMO and LUMO analysis of 1,5-dimethyl napthalene by density functional method.
abstract: The Fourier-transform infrared and FT-Raman spectra of 1,5-Dimethyl Napthalene (15DMN) was recorded in the region 4000-400cm(-1) and 3500-50cm(-1) respectively. Quantum chemical calculations of energies, geometrical structure and vibrational wavenumbers of 6M2C were carried out by density functional theory (DFT/B3LYP) method with 6-311++G(d,p) basis set. The difference between the observed and scaled wavenumber values of most of the fundamentals is very small. The values of the total dipole moment (μ) and the first order hyperpolarizability (β) of the investigated compound were computed using B3LYP/6-311++G(d,p) calculations. The calculated results also show that 15DMN might have microscopic non-linear optical, MESP, NBO analysis with non-zero values. A detailed interpretation of infrared and Raman spectra of 15DMN is also reported. The calculated HOMO7-LUMO energy gap shows that charge transfer occur within the molecule. The molecular electrostatic potential map shows that the negative potential sites are on the electronegative atoms as well as the positive potential sites are around the hydrogen atoms.
authors.affiliation: Department of Physics, A.A. Government Arts College, Musiri, Tiruchirappalli 621201, TN, India. Electronic address: jjmarivu@yahoo.co.in.
authors.forename: M
authors.initials: M
authors.lastname: Arivazhagan
authors.affiliation: Department of Physics, Jeppiaar Engineering College, Chennai 600109, TN, India.
authors.forename: V P
authors.initials: VP
authors.lastname: Subhasini
authors.affiliation: Department of Physics, Saranathan Engineering College, Tiruchirappalli, TN, India.
authors.forename: R
authors.initials: R
authors.lastname: Kavitha
authors.affiliation: Department of School Education, Government Higher Sec. School, Malvai, Tiruchirappali-621652, TN, India.
authors.forename: R
authors.initials: R
authors.lastname: Senthilkumar
mesh_terms: D008745:Methylation; D008958:Models, Molecular; D008968:Molecular Conformation; D009281:Naphthalenes / Q000737:chemistry*; D011789:Quantum Theory; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman
chemical_list: D009281:Naphthalenes
keywords: 1,5-Dimethyl napthalene; DFT; FT-IR; FT-Raman; HOMO; LUMO