%A Labidi, N. S. %D 2021 %T Electron Correlation Effects and Dipolar/Octupolar Contribution on the First Hyperpolarizability of Push-Pull Oligomer Systems %B 2021 %9 %! Electron Correlation Effects and Dipolar/Octupolar Contribution on the First Hyperpolarizability of Push-Pull Oligomer Systems %K %X The hyper-Rayleigh scattering first hyperpolarizabilities β HRS  of a series of push-pull oligomer are studied using theoretical chemistry methods. Several DFT XC functionals have been used while reliable atomic basis sets have been selected for their evaluations. The behavior of hyper-Rayleigh scattering first hyperpolarizability is studied as a function the basis sets, of electron correlation, of solvent as well as the strength of the electron donor groups to address structure-property relationships.  It has been observed that the electron correlation effects are huge, the Møller–Plesset results reproduces the values of the first hyperpolarizability obtained with the reference CCSD(T) level. Among density functional theory exchange-correlation functionals, B3LYP, M062X and CAM-B3LYP are reliable to the MP2 characterized static and dynamic first hyperpolarizability. Finally, the EFISHG first hyperpolarizabilities values put on view different ordering and present more delicate variations as a function of the substituted oligomers. The depolarization ratios follow an opposite ordering as the anisotropy factors while they display an extensive separation dipolar-octupolar character. %U http://www.revistacubanadefisica.org/index.php/rcf/article/view?path= %J Revista Cubana de Física %0 Journal Article %& 94 %P 9 %V 38 %N 2 %@ 2224-7939 %8 2021-12-15 %7 2021-12-15