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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]

A new nonlinear optical chromophore with strong electron-withdrawing acceptor and rigid-flexible dendron was synthesized. An electro-optic (EO) attenuated total reflectance modulator was prepared to measure the EO coefficient of the films. Modification of the tricyanopyrroline chromophore with rigid-flexible dendron group provided reduction of dipole-dipole interactions and improvement of its solubility. As the chromophore loading increased, there was a great improvement on the macroscopic EO response of the polymeric materials obtained by incorporating this chromophore as a guest in amorphous polycarbonate. The largest EO coefficient was 42 pm/V at 1310 nm. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Novel organic second-order nonlinear optical (NLO) chromophore with a large flexible rigid isolated group was prepared. The NLO properties were measured in solution and PMMA polymer films. The first order hyperpolarizabilities were equal to 4×10−28 esu and 7×10−29 esu at 1064nm Nd:YAG laser wavelength in solvent and polymer, respectively and these results are in agreement with quantum chemical calculations. Moreover, this chromophore has high thermal stability when thermal decomposition temperature is 270°C. Electrostatic interactions of the chromophores were effectively reduced by isolated group. No apparent change of the shape of UV absorption spectra versus concentration was found. [Copyright &y& Elsevier]

Novel nonlinear optical (NLO) chromophore using benzo[b]furan moiety and trifluoromethyl-substituted tricyanofuran as the electron donor and acceptor respectively was designed and prepared. The structure of the novel chromophore was determined by NMR spectra, and the photophysical properties were studied via UV-vis spectra. The thermal decomposition temperature (T d)value of the obtained NLO chromophore reached to 212 °C, which endow the chromophore with good thermal stability during the materials processing. The nonlinearity of the chromophore was evaluated through theoretical calculation and electro-optic (EO) activity test, and the highest EO coefficient (r 33) was determined to 28 pm/V at the loading density of 25 wt% in polymethyl methacrylate. • Novel benzofuran-based nonlinear optical chromophore was designed and synthesized. • The acceptor was unexpected linked to the β -position of furan in the chromophore. • The present chromophore exhibited go0d thermal stability (T d reached to 212 °C). • The maximum EO coefficient of the reported chromophore reached to 28 p.m./V. [ABSTRACT FROM AUTHOR]

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]

• Novel FTC-type NLO chromophore is designed to developing high performance EO material. • The obtained NLO chromophore possesses good film forming ability and obvious T g near 75 °C. • As EO molecular glass, the poled pure chromophore film displayed the r 33 value of 160 pm/V. To explore the simple strategy for developing excellent electro-optic (EO) materials, a monolithic EO molecular glass (EOMG1) based on thiophene π-conjugation and tricyanofuran acceptor (FTC) was synthesized. A tert -butyldiphenylsilyl (TBDPS) group was introduced to the FTC-based nonlinear optic (NLO) chromophore. The glass transition temperature (T g) of the amorphous films was near 75 ℃, confirmed EOMG1 's glassy state. The theoretical calculation shows that the first hyperpolarizability (β) and dipole moment (μ) of EOMG 1 were calculated to 584 × 10−30esu and 20.73 D. After poling, the poled films EOMG1 diplay large EO activity (r 33) of 160 pm/V at 1310 nm. The r 33 value is greatly enhanced compared to the reported side-chain EO polymer containing the similar FTC-type NLO chromophore due to the increased loading density of the pure chromophore films and the TBDPS group's role of effective isolation. [ABSTRACT FROM AUTHOR]