Synthesis, Characterization, Absorbance, Fluorescence and Non Linear Optical Properties of Some Donor Acceptor Chromophores

Three carbazole chromophores featuring dicyano, cyano, ethyl acetate and dimethyl acetate groups as an acceptor moiety with a <TEX>${\pi}$</TEX>-conjugated spacer and <TEX>$N$</TEX>-methyl dibenzo[<TEX>$b$</TEX>]pyrole as donor were synthesized by Knovenagel condensation and characterized by IR, <TEX>$^1HNMR$</TEX>, <TEX>$^{13}CNMR$</TEX>, UV-vis, fluorescence spectroscopy, electrochemistry and theoretical B3LYP/6-<TEX>$311G^*$</TEX> level whilst NLO properties and spectroscopic quantities were calculated. Calculations showed remarkable trend with HOMO located on the donor moiety and LUMO on the acceptors dicyano methylene, cyano, ethyl acetate methylene and dimethyl acetate methylene. In agreement with the calculations, solvatochromic, behavior intramolecular charge transfer band was observed in the visible region.