LAUSR

Abstract In order to further investigate the dependence of optical limiting properties on the molecular structures, especially the strong intermolecular effects, such as the effects of hydrogen bond, dipole-dipole interaction and the influences of their synergistic effect on the optical limiting properties, three polar D-π-A conjugated azobenzene derivatives (N1, N2 and N3) with different hydrogen-bond recognition abilities were designed and synthesized. Their molecular structure and properties were characterized and evaluated by infrared spectroscopy, thermogravimetric analysis, ultraviolet–visible spectrometry, and Z-scan technique with a Q-swithed ps Nd:YAG laser system continuum. The mechanism of optical limiting enhancement is investigated by theoretical calculation and experimental measurement based on molecular self-assembly synergistic effect of hydrogen bond and dipole-dipole interaction. The results show that the nonlinear optical properties of these polar D-π-A conjugated nonlinear optical materials were obviously affected by organic molecular structure, strong intermolecular interaction and their synergetic enhancement effect.