4-Dimethylamino-4-nitrostilbene

It should be possible in principle to determine the orientation of chromophores in a single monolayer on an OWG by the absorption of transverse electric (TE, s-polarized) and transverse magnetic (TM, p-polarized) modes laser. Swalen et al. [109] reported that much stronger absorption was observed for a thin evaporated film of 4-dimethylamino-4 -nitrostilbene with the TM mode and for seven monolayers of cyanine dyes with the TE mode. These results corresponded... 

The results from EFISH experiments are listed in Table IV along with the FF predictions. We note that the our measured values for 4-dimethylamino-4 -nitrostilbene (DANS) and 4-dimethylamino-4 -nitroazobenzene are consistent with previously published work (26,27). The theoretical predictions discussed previously show an excellent correlation with the actual measured values for (Mg)zPz. As predicted the nonlinearities of nitro-containing compounds are larger... 

To determine whether NLO chromophores can be immobilized in highly cross-linked matrices, experiments were carried out in which the high- molecules 4-(dimethylamino)-4 -nitrostilbene (DANS, 3) and Disperse Orange 1 (DOI, 4) were dispersed in an optical grade epoxy resin,... 

Molecules such as 4 -dimethylamino-4-nitrostilbene ( DANS , 1) possess the necessary electronic structure, and have very large p... 

Dopant orientation during and following electric field-induced poling can be studied continuously and in real time in order to examine the microenvironment surrounding the dopants in terms of the polymer relaxations and the applied corona field. In the results presented below, the SHG of 4-dimethylamino-4 -nitrostilbene (DANS) dispersed in polystyrene (PS) or poly(methyl methacrylate) (PMMA) matrices has been examined in corona poled films as a function of temperature in order to understand the effect of thermal conditions on the temporal stability of the dopant orientation. 

Fig. 3 cttpa variations with the number of excited states involved in the SOS expression (3) for the 4-dimethylamino-4-nitrostilbene and the dimethylamino)- -stilbene... 

The intramolecular charge-transfer state of 4-dimethylamino-4 -nitrostilbene has also been examined recently with TRIR methods (a) H. Okamoto, M. Tasumi, Chem. Phys. Lett. 1996, 256, 502. (b) H. Okamoto, M. Tasumi, Laser Chem. 1999, 79, 363. 

Zhang, Q., M. Canva, and G. Stegeman. 1998. Wavelength dependence of 4-dimethylamino-4 -nitrostilbene polymer thin film photodegradation. Appl Phys Lett 73 912-914. 

Figure 17 Electrochromic measurements of DANS (4-dimethylamino-4 -nitrostilbene) in PMMA at 125 °C. The change in absorption is measured at a wavelength of 435 nm.

In this chapter, we present the fabrication parameters and optical performances of the packaged polymeric MZ waveguide modulator for photonic applications using a polymethyl methacrylate (PMMA-based side-chain polymer with 4-dimethylamino-4 -nitrostilbene (DANS). We discuss the design considerations for single-mode propagation at a wavelength of 1.3 fim in relation to the fabrication sequence. In particular, we discuss the optical power stability of our devices in detail. 

Okamoto, H. and Tasumi, M. (1996) Picosecond transient infrared spectroscopy of electronically excited 4-dimethylamino-4 -nitrostilbene in the fingerprint region (1640-940cm ). Chem. Phys. Lett., 256, 502-508. 

A comprehensive comparison among different expressions was done by Koutek, in a remarkable paper of the late 1970s [201] on the basis of the data available for 9 compounds, viz. carbazole, indole, l,3-diphenyl-2-pyrazoline, (hexamethyl-benzene + tetrachlorophthalic anhydride) CT-complex, 4-amino-4 -nitrostilbene, 4-dimethylamino-benzonitrile, 4-dimethylamino-4 -nitrostilbene, 4-dimethylamino-co-nitrostyrene, and 4-dimethylamino-benzylidene-4 -nitroaniline. Unfortunately, the analysis was limited to neutral molecules characterised by the presence of a symmetry axis, or at least by expected co-directional electric dipole moment vectors. 

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