title: Static and dynamic electronic (hyper)polarizabilities of dimethylnaphthalene isomers: characterization of spatial contributions by density analysis.
abstract: Static and frequency-dependent electronic (hyper)polarizabilities of the dimethylnaphthalene (DMN) isomers were computed in vacuum using the Coulomb-attenuating Density Functional Theory method. The nonlinear optical Second Harmonic Generation (SHG) and Electro-Optical Pockels Effect (EOPE) were investigated at the characteristic Nd:YAG laser wavelength of 1064 nm. The response electric properties especially the longitudinal polarizability, polarizability anisotropy, and first-order hyperpolarizability are significantly affected by the position of the methyl groups. The SHG and EOPE techniques can be potentially useful to discriminate the α,α-DMN isomers (2,6-DMN < 2,7-DMN < 2,3-DMN) as well as the β,β-DMN isomers (1,5-DMN < 1,4-DMN < 1,8-DMN). The (hyper)polarizability differences among the investigated DMNs were elucidated through density analysis calculations. The predicted polarizabilities exhibit good linear relationships with the experimental first-order biomass-normalized rate coefficient, a physicochemical property connected to the rates of biodegradation processes of polycyclic aromatic hydrocarbons.
authors.affiliation: Department of Chemistry, University of Catania, Viale A. Doria 6, 95125 Catania, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Alparone
mesh_terms: D004583:Electrons; D007536:Isomerism; D009281:Naphthalenes / Q000737:chemistry*; D055672:Static Electricity
chemical_list: D009281:Naphthalenes; C028519:2,6-dimethylnaphthalene