Solvent Effect on Hyper-Rayleigh Scattering (HRS) First Hyperpolarizability of Substituted Polyene: Ab Initio Study

The first hyperpolarizabilities β_HRS of substituted hexatriene molecules have been carried out to assess the effects of the bridge length, of the frequency dispersion as well as the solvent polarity. These calculations confirm the particular behaviour of the first hyperpolarizability β_HRS, depolarization ratio and the anisotropy factor as a function of the incident light frequency and solvent polarity. The impact of the solvent and expanding the π-conjugated limit to improve the β_HRS. Finally, the interplay between β_HRS and β_//, β_vec, d_N...N, E_gap and the Kirkwood–Onsager factor [(ε–1)/(2ε + 1)] was established.