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A series of triphenylamino (TPA)-chalcones and triphenylamino-β-arylchalcones, displaying either D-π-D or D-π-A architecture, were synthesized through aldol condensations and Heck reactions. The chalcone derivatives display intense absorption bands ranging from 389 to 432 nm and molar extinction coefficients of ca. 10 5 L mol-1 cm-1 corresponding to π-π* electronic transitions. The photoluminescence emissions are peaked between 470 and 563 nm with large Stokes shifts (80-131 nm), attributed to charge transfer in the excited state. The dyes present low fluorescence quantum yields, which is attributed to radiationless excited state deactivation related to aryl rings rotation. Spectroscopic and electrochemical methods were used to determine the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels. Both optical and electrochemical properties of the TPA-chalcone derivatives are considerably affected by the substitution pattern of the chalcones aryl rings and also by the β-arylation of the olefin moiety.

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The search for optical materials, particularly organic compounds, is still an attractive and essential field for developing several photonic devices and applications. For example, some applications are based on light scattering with twice the energy of the incoming photon for selected compounds, that is, the nonlinear optical effect related to the second-order susceptibility term from the electronic polarization expression. The microscopic interpretation of this phenomenon is called the first-order molecular hyperpolarizability or incoherent second harmonic generation of light. Understanding such phenomena as a function of the incoming wavelength is crucial to improving the optical response of future materials. Still, the experimental apparatus, hyper-Rayleigh scattering, apparently simple, is indeed a challenging task. Therefore, we proposed a proper alternative to obtain the dispersion of the first-order hyperpolarizability using the well-known one-and two-photon absorption techniques. By the spectral analysis of both the spectra, we gathered spectroscopic parameters and applied them for predicting the first-order hyperpolarizability dispersion. This prediction is based on an n-level energy system, taking into account the position and magnitude of transition dipole moments and the difference between the permanent dipole moment of the n-excited states. Moreover, using the presented method, we can avoid underestimating the firstorder hyperpolarizability by not suppressing higher-energy transitions. Quantum chemical calculations and the hyper-Rayleigh scattering technique were used to validate the proposed method.