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SONG Hua-Can WEN Huan LIANG Dong SUN Yi-Feng 《有机化学》2003,23(Z1):411-412
It has attracted a lot of attentions to synthesize and investigate the behaviors of organic second-order nonlinear optical (NLO) materials. [1,2] We have ever reported that acridine derivatives ,[3] 4-substituted-benzylideneoxazol-5(4H)-one[4] and 4,4′-di-styryl-biphenyl derivatives[5] possess good second-order NLO properties. Coumarin derivatives are good organic optical materials and azobenzene derivatives possess a higher second-order nonlinear polarization values, however, there are few reports about the study on the synthetic method, optical behavior, especially,second-order NLO properties of 3-substitued-6-(substituted-phenylazo) coumarin derivatives. Therefore, a series of the following compounds were prepared in order to investigate their NLO behavior. 相似文献
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Recent advances in poled amorphous polymers for second-order nonlinear optics are discussed with emphasis on stabilizing the frozen-in nonlinearity via chemical crosslinking under electric fields. Specific examples of a linear polymer and a crosslinked polymer, both with nitroaniline-type chromophores covalently attached as side groups, are presented and compared in their glass transition behavior, linear optical properties, poling dynamics, and stability of frozen-in nonlinearity. It is demonstrated that by employing chemical crosslinking under electric fields one can prepare highly efficient and stable poled polymers that exhibit no decay in nonlinearity at ambient conditions and no apparent tendency of decay even at 85°C as well as excellent optical properties. The historical development of organic materials for second-order nonlinear optics and recent advances in device fabrication based on poled polymers are also discussed briefly. 相似文献
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The equilibrium geometries of four asymmetric spirosilabifluorene derivatives are optimized by means of the DFT/B3LYP method with the 6-31G* basis sets in this paper. On the basis of the optimized structures, the electronic structure and second-order nonlinear optical properties are calculated by using time-dependent density-functional theory (TDDFT) based on the 6-31G* level combined with the sum-over-states (SOS) method. The results show that these compounds possess remarkably larger molecular second-order polarizabilities than typical organometallic and organic compounds, and replacement of a carbon atom with nitrogen within the conjugated substituent has a great influence on the second-order nonlinear optical properties. Analysis of the main contributions to the second-order polarizability suggests that charge transfer from the z-axis directions plays a key role in the nonlinear optical response. These compounds have a possibility to be excellent second-order nonlinear optical (NLO) materials from the standpoint of large beta values, small dipole moment, high transparency, and small dispersion behaviors. 相似文献
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The dipole polarizabilities, second-order polarizabilities, and origin of second-order nonlinear optical (NLO) properties of trisorganotin-substituted beta-Keggin polyoxotungstate [XW9O37(SnR)3](11-n)- (X = P, Si, Ge, R = Ph; X = Si, R = PhNO2, PhCCPh) have been investigated by using time-dependent density functional response theory. This class of organic-inorganic hybrid complexes possesses a remarkably large molecular second-order NLO response, especially for [SiW9O37(SnPhCCPh)3]7- (system 5) with the static second-order polarizability (beta(vec)) computed to be 1569.66 x 10(-30) esu. Thus, these complexes have the possibility to be excellent second-order nonlinear optical materials. Analysis of the major contributions to the beta(vec) value suggests that the charge transfer from the heteropolyanion to the organic segment along the z-axis plays the key role in the NLO response of [XW9O37(SnR)3](11-n)-. The computed beta(vec) values increase as a heavy central heteroatom changes in the order Ge > Si > P. Furthermore, nitro substitution on the aryl segment and the lengthening of organostannic pi-conjugation are more important in enhancing the optical nonlinearity, especially for the latter factor. The present investigation provides important insight into the origin of the NLO properties of trisorganotin-substituted heteropolyoxotungstate. 相似文献
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Sutiyao Marturunkakul Jeng-I Chen Lian Li Jayant Kumar Sukant K. Tripathy 《先进技术聚合物》1996,7(4):303-308
There has been a tremendous recent interest in the development of second-order nonlinear optical (NLO) polymeric materials for photonic applications. However, a major drawback of second-order NLO polymers that prevents them from being used in device applications is the instability of their electric field induced dipolar alignment. The randomization of the dipole orientation leads to the decay of second-order optical nonlinearities. Numerous efforts have been made to increase the stability of the second-order NLO properties of polymers. The search for new approaches to develop NLO polymers with optimal properties has been an active research area since the past decade. A novel approach, combining the hybrid properties of high glass transition temperatures, extensively extensively crosslinked networks and permanent entanglements, based on interpenetrating polymer networks (IPN) is introduced to develop stable second-order NLO materials. Two types of IPN systems are prepared and their properties are investigated. The designing criteria and the rationale for the selection of polymers are discussed. The IPN samples show excellent temporal stability at elevated temperatures. Long-term stability of the optical nonlinearity at 100°C has been observed in these materials. Temporal stability of the NLO properties of these IPNs is synergistically enhanced. Relaxation behavior of the optical nonlinearity of an IPN system has been studied and compared with that of a typical guest/host system. The improved temporal stability of the second-order NLO properties of this IPN system is a result of the combination of the high rigidity of the polymer backbones, crosslinked matrices and permanent entanglements of the polymer networks. A slight modification of the chemical structure resulted in an improvement of the optical quality of the sample. 相似文献
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通过重氮化偶合反应和羟醛缩合反应合成了以偶氮苯为共轭桥、以2,2,3-三甲基-4-氰基-5-二氰基亚甲基-2,5-二氢呋喃为电子受体, 而给体分别为二甲氨基和二乙氨基的两种有机非线性光学生色团分子MFNC和EFNC. 利用IR、1H NMR和元素分析对分子的结构进行了表征. TGA和DSC测试发现, MFNC的热稳定性略好于EFNC, 其热分解温度最高达266 ℃. 通过测定两种材料在氯仿、丙酮和DMSO中的紫外-可见光谱, 用溶致变色法计算得到两种材料在激光波长为1064 nm处的二阶非线性品质系数μgβ, 对比发现EFNC的μgβ值高于MFNC, 其值达59706×10-48 esu(1 esu=3.34×10-10C). 相似文献
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David J. Williams 《Angewandte Chemie (International ed. in English)》1984,23(9):690-703
Nonlinear optical properties are a sensitive probe of the electronic and solid-state structure of organic compounds and as a consequence find various applications in many areas of optoelectronics including optical communications, laser scanning and control functions, and integrated optics technology. Because of their strongly delocalized π electronic systems, polymeric and non-polymeric aromatic compounds show highly nonlinear optical effects. Nowadays, polymer chemists are able to tailor specific materials properties for various applications. Some organic substances with π electronic systems exhibit the largest known nonlinear coefficients, often considerably larger than those of the more conventional inorganic dielectrics and semiconductors, and thus show promise for thin-film fabrication, allowing the enormous function and cost advantages of integrated electronic circuitry. The electronic origins of nonlinear optical effects in organic π electronic systems are reviewed, with special emphasis being given to second-order nonlinear optical effects. Methods for measuring nonlinear optical responses are outlined, and the critical relationships of the propagation characteristics of light to observed nonlinear optical effects and to solid-state structure are discussed. Finally, the synthesis and characterization of organic crystals and polymer films with large second-order optical nonlinearities are summarized. 相似文献
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The dipole polarizability and second-order polarizability of recently synthesized (1,3-di-ter-butylimidazol-2-ylidine) gold complexes [(Bu2t Im)AuX] (X=halogen) were investigated by using time-dependent density-functional theory combined with sum-over-states method. We have discovered that these complexes possess remarkably larger molecular second-order polarizability compared with the organometallic and organic complexes. The value of the second-order polarizability increases in the order of F相似文献
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SONG Qing-Bao WU Xiao-Li SHEN Tian-Hua YANG Shang-Dong QIANG Gen-Rong WANG Yong-Qiang MA Yong-Xiang 《有机化学》2003,23(Z1):361-362
Last two decades, molecular-based second-order nonlinear optical (NLO) chromo-phores[1,2] have attracted much attention because of their potential applications in emerging opto-electronic technologies. These efforts have mainly focused on organic systems. More recently, organometallic molecules have been investigated as well. In comparison to common organic molecules, they offer a large variety of novel structures. The possibility of high environ mental stability, and diversity of turnable electronic behaviors by virtue of the coordinated metal center of which might bring about NLO materials with unique characteristics such as magnetic and electro-chemical properties. 相似文献
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Asselberghs I Flors C Ferrighi L Botek E Champagne B Mizuno H Ando R Miyawaki A Hofkens J Van der Auweraer M Clays K 《Journal of the American Chemical Society》2008,130(46):15713-15719
The second-order nonlinear optical properties of green fluorescent proteins (GFPs), such as the photoswitchable Dronpa and enhanced GFP (EGFP), have been studied at both the theoretical and experimental levels. In the case of Dronpa, both approaches are consistent in showing the rather counterintuitive result of a larger second-order nonlinear polarizability (or first hyperpolarizability, beta) for the protonated state, which has a higher transition energy, than for the deprotonated, fluorescent state with its absorption at lower energy. Moreover, the value of beta for the protonated form of Dronpa is among the highest reported for proteins. In addition to the pH dependence, we have found a wavelength dependence in the beta values. These properties are essential for the practical use of Dronpa or other GFP-like fluorescent proteins as second-order nonlinear fluorophores for symmetry-sensitive nonlinear microscopy imaging and as nonlinear optical sensors for electrophysiological processes. An accurate value of the first hyperpolarizability is also essential for any qualitative analysis of the nonlinear images. 相似文献
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取代吡啶系列分子的光谱和二阶非线性光学性质的理论研究 总被引:11,自引:4,他引:7
采用AM1方法优化分子构型,用ZINDO方法研究了氨基、硝基取代的吡啶系列分子的电子光谱,并在此基础上用自编程序计算了这些分子的二阶非线性光学系数,对取代吡啶系列分子的二阶非线性光学系数的影响因素进行了探讨,并在微观上给予了解释。 相似文献
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在ZINDO方法基础上,按完全态求和(SOS)公式编制了计算分子二阶非线性光学系数βijk、βμ的程序,研究了各种吩噻嗪侧环取代衍生物的结构和二阶非线性光学性质,结论是侧环上推、拉电子取代基(不太弱)对增大二阶光学非线性都有利,扩大共轭范围也对增大二阶光学非线性有利,并对上述结果在微观上给予了解释。 相似文献
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在ZINDO方法基础上,按完全态求和(SOS)公式编制了计算分子二阶非线性光学系数βijk、βu的程序.研究了不同取代基在5,12-二硫杂-7,14-二氮杂-5,7,12,14-四氢并五苯侧环取代衍生物及相关化合物的结构、光谱和二阶非线性光学性质。结果表明:侧环上取代推、拉电于基团对增大二阶光学非线性都有利;分子共平面,共轭作用强,对增大二阶光学非线性有利. 相似文献
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Two-dimensional materials have recently attracted attention due to their unique physical properties and promising applications. This work reports the electronic, linear and second-order nonlinear optical properties of aluminum nitride (AlN) monolayer by using a real-time first-principles approach based on Green's function theory. In this approach, quasi-particle corrections, crystal local field effects, and excitonic contributions are considered for investigating the linear and nonlinear responses. As a two-dimensional material with a wide direct gap of around 6.45 eV, the AlN monolayer exhibits strong resonances of absorption and second-harmonic spectra in the ultraviolet range. In the transparent spectral range from blue to deep ultraviolet (2.8–5.3 eV), strong peaks of second-order nonlinear susceptibility appear in the AlN monolayer with a large peak value of around 430 pm/V, which is one or two orders-of-magnitude larger than the nonlinear materials used in the ultraviolet range. The results presented in this work will find important applications for nonlinear imaging, spectroscopy, and nonlinear nanophotonics in the ultraviolet range. 相似文献