Synthesis, characterization and two-photon absorption based broadband optical limiting in diarylideneacetone derivative

A donor-pi-acceptor-pi-donor (D-pi-A-pi-D) type Bis-Chalcone, (1E,4E)-1,5-di-2-thienylpenta-1,4-dien3-one (D2TDO) was synthesized by Claisen-Schmidt reaction. Structural characterization was done with the help of UV, FT-IR, H-1 NMR, C-13 NMR and Mass Spectroscopic techniques. Through gravity settling method, a homogenous film of D2TDO with 65 mu m thickness was made in poly(methylmethacrylate) matrix. The third-order absorptive nonlinearity and resultant optical limiting behavior of the D2TDO film were studied by employing open aperture z-scan method in both nanosecond and femtosecond excitation regimes. Through numerical simulations, the mechanism of nonlinear absorption was found to be a two-photon absorption process with broadband response. The optical limiting performance of the molecule has its origin from the molecule's peculiar D-pi-A-pi-D structure which allows for a greater extent of pi electron delocalization due to a strong pi-electron donor like thiophene. (C) 2012 Elsevier B.V. All rights reserved.