Optical and nonlinear optical properties of new Schiff's bases: experimental versus theoretical study of inclusion interactions

Experimentally and theoretically were studied the physical properties of 19 new Schiff's bases and their different protonated forms, depending on reaction conditions. It was elucidated the correlation between the type of molecular architecture, substituents and pH of the medium on first hyperpolarizability (beta) with regard to the potential application of these compounds as organic nonlinear optical materials. The structure and optical properties were also studied, comparing quantum chemical data and experimental results from the mass spectrometry, electronic absorption, diffuse reflectance, and fluorescence spectroscopy, vibrational spectroscopy in condense phase, nuclear magnetic resonance, as well as thermal methods.