Synthesis and characterization of carbazole derived nonlinear optical dyes

Three kinds of carbazole derived dyes, Caz-MN, Caz-Fu, and Caz-Vm-MN of push–pull molecules were synthesized and their nonlinear optical properties measured. The second harmonic generation (SHG) coefficients, d33, of Caz-Fu/PVK[poly(9-vinylcarbazole)] (0.1:0.9) and Caz-Vm-MN/PVK (0.1:0.9) were 2.06 × 10−9 esu and 7.3 × 10−9 esu, respectively. The electro-optic coefficients (r33) of these PVK blends with dyes were also observed to be 1.23 pm/V, 4.03 pm/V at a wavelength of 632.8 nm. The synthesized novel carbazole based dyes Caz-MN, Caz-Fu, and Caz-Vm-MN were characterized by means of 1H NMR spectroscopy, IR spectroscopy, thermogravimetric analysis, electro-optic coefficients (r33), and their NLO properties were evaluated by Maker fringe method.