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Abstract: A novel nunchaku-like organic second order nonlinear optical chromophore containing a D–π–A backbone and a rigid biphenylene unit was prepared. The UV–vis absorption spectra studies demonstrated that the large rigid structure could suppress dipole–dipole interactions effectively. The electro-optic coefficient of a poled film containing 20% wt of the new dye doped in amorphous polycarbonate afforded a value of 39 pm/V at 1310 nm. Compared with results obtained from a similar D–π–A chromophore without the rigid isolated group, the new dye gave better performance. Moreover, the electro-optic film prepared with the new dye gave greater temporal stability, compared to a similar D–π–A doped poled film that was reported previously. These results indicated that the introduction of a biphenylene group could effectively reduce the intermolecular electrostatic interactions and aid the alignment of the chromophores. [Copyright &y& Elsevier]

Abstract: A series of novel second-order nonlinear optical chromophores containing additional heteroatoms in donor moieties has been synthesized and systematically characterized. The resulting nonlinear optical chromophores exhibited both good thermal stability (the decomposition temperature in the range of 249 °C–275 °C) and good solubility in common organic solvents such as chloroform, acetone and N, N-dimethyl formamide. In order to investigate the influence of additional heteroatom on the electro-optic activities, UV–Vis spectra and density functional theory calculations were carried out. The results revealed that the donor derived from m-phenylenediamine had higher electron density compared with other three donors. As to electro-optic activities, the doped polymer film-C displayed the highest electro-optic coefficient value of 31 pm/v at the doping concentration of 20 wt%. All these results indicated that the nonlinear optical activities could be enhanced by introducing suitable additional heteroatoms into donor moiety. [Copyright &y& Elsevier]