Effect of Branching on Two-Photon Absorption in Triphenylbenzene Derivatives

Claudine Katan ‘s present address : CNRS UMR6082 FOTON, INSA de Rennes, 20 avenue des Buttes de Coësmes, CS 70839, 35708 RENNES cedex 7, FranceInternational audienceThe photophysical and linear and nonlinear spectral properties of octupolar compounds with a triphenylbenzene core are investigated and compared with properties of corresponding dipolar branches. A correlation is found between the solvatochromic behavior and the two-photon absorption cross section. Moreover, the nature of the core is found to be responsible for the nature of the coupling between branches; in the studied case only (weak) electrostatic interactions are effective, while other cores, like the triphenylamine moiety, are able to promote coherent coupling between the branches, leading to strongly nonadditive properties