Interpreting the First-Order Electronic Hyperpolarizability for a Series of Octupolar Push-Pull Triarylamine Molecules Containing Trifluoromethyl

Autor(es)

Vivas, Marcelo G. ^{[1, 2]} ; Silva, Daniel L. ^[3] ; Rodriguez, Ruben D. F. ^[1] ; Canuto, Sylvio ^[4] ; Malinge, Jeremy ^[5] ; Ishow, Elena ^[6] ; Mendonca, Cleber R. ^[1] ; De Boni, Leonardo ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Fis Sao Carlos, BR-13560970 Sao Carlos, SP - Brazil

^[2] Univ Fed Alfenas, Inst Ciencia Tecnol, BR-37715400 Pocos De Caldas, MG - Brazil

^[3] Univ Fed Sao Carlos, Dept Ciencias Nat Matemat & Educ, BR-13600970 Araras, SP - Brazil

^[4] Univ Sao Paulo, Inst Fis, BR-05314970 Sao Paulo, SP - Brazil

^[5] Ecole Normale Super, PPSM UMR CNRS 8531, F-94235 Cachan - France

^[6] Univ Nantes, CEISAM UMR CNRS 6230, F-44322 Nantes - France

• Tipo de documento: Artigo Científico
• Fonte: Journal of Physical Chemistry C; v. 119, n. 22, p. 12589-12597, JUN 4 2015.
• Citações Web of Science: 8

Resumo

In this present paper, we investigate the relationship between the dynamic first-order hyperpolarizability (DFH, or beta(HRS)) of a triarylamine core bearing two 3,3'-bis(trifluoromethyl)phenyl arms and the nature of a third group containing distinct electron withdrawing strength (H < CN < CHO < NO2 < Cyet < Vin). For that, we have combined hyper-Rayleigh scattering (HRS) experiments with picosecond pulse train at 1064 nm and quantum chemical calculations at the density functional theory (DFT) level. The beta(HRS) values exhibited pronounced enhancement from 56 x 10(-30) cm(5)/esu (EWG = CN) up to similar to 400 X 10(-30) cm(5)/esu (EWG = Vin) due to the increase in the degree of donor-acceptor charge transfer concomitant with the intensification of the resonance enhancement effect observed when the scattered photon (2w = 532 nm) approaches, in energy, the lowest energy band of chromophores. Furthermore, our experimental results suggest that the CF3 group has a significant effect on the beta(HRS), since we observed a considerable increase in this parameter (at least 30% higher) for CF(3)EWG molecules as compared to their homologous tBu.EWG derivatives, recently investigated. Finally, the beta(HRS) results were compared with theoretical results provided by the coupled perturbed Hartree-Fock method implemented at the DFT level of theory and combined with a polarizable continuum model to take into account the solvent environment. The theoretical results allowed us to evaluate the effects of solvent-induced polarization and frequency dispersion on the first-order hyperpolarizability of the molecules and their molecular anisotropy (or dipolar/octupolar contributions). (AU)

• Processo FAPESP: 09/11810-8 - Estudo do efeito de solvente sobre os espectros da absorção de um e dois fótons de moléculas orgânicas conjugadas.
• Beneficiário: Daniel Luiz da Silva
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 11/12399-0 - Aplicações de pulsos de femtossegundos em óptica não linear: espectroscopia, formatação de pulsos e microfabricação
• Beneficiário: Cleber Renato Mendonça
• Modalidade de apoio: Auxílio à Pesquisa - Temático