Platinum poly-yne

Guha, S., Frazier, C. C., Porter, P. L., Kang, K., Finberg, S. E., Measurement of the 3rd-order hyperpolarizability of platinum poly-ynes. Optics Letters 1989,14, 952-954. 

Wong, W.-Y. Chan. S.-M. Choi, K.-H. Cheah, K.-W. Chan, W.-K. Synthesis, optical and photoconduction properties of platinum poly-yne polymers functionalized with electron-donating and electron-withdrawing bithiazole units. Macromol. Rapid Commun. 2000, 21, 453-457. 

Detailed studies have been performed on the photophysics of a range of Pt poly-ynes [68, 75-77], and the energy-gap law for triplet states in a series of platinum poly-ynes has been established [78]. Convincing evidence for Jt-conjugation between metal sites in the main chain has been provided by some of the experiments [75]. The photophysics of polymers with fluorene and carbazole spacers has also been investigated in depth, and the studies indicate that the singlet state extends over more than one repeat unit whereas the triplet state is strongly localized [79]. 

The platinum poly-ynes show attractive physical properties, third-order optical non-linearity [107-109] and the formation of lyotropic liquid crystalline... 

NONLINEAR OPTICAL THIN FILMS OF PLATINUM POLY-YNES... 

The imaginary part of the third-order hyperpolarizability (y) was measured for a series of platinum poly-ynes in both solution and thin-film form, and for a group of related platinum-organic species. 

The platinum poly-yne films presented here have figures of merit similar to that of film 1 (Table 2), a well-known film with high nonlinearity. While the nonlinearities of the platinum poly-yne films are usually higher than that of film i, the absorption coefficients, a, are also larger. 

Recently, experimental data of S for various liquid-crystalline polymer solutions have become available. Figure 12 illustrates the concentration dependence of S for three polymer liquid crystal systems (a) PBLG-DMF [92,93], (b) PHIC-toluene [94], and (c) poly(yne)-platinum polymer (PYPt)-trichloro-ethane (TCE) [33]. For systems (a) and (c), with the alignment made by... 

In spite of the presence of metal-carbon o-bonds and carbon-carbon triple bonds in the backbone, the metal-poly-yne polymers are fairly stable to air in the solid state and show considerably good thermal stability (Table 6). The platinum-containing... 

In the 1970s, Hagihara and coworkers reported the synthesis of oligomeric and polymeric poly(metal acetylides), also called poly-ynes. containing transition metals in the main chain. ] Conjugated poly-ynes containing platinum or palladiuin complexes in their backbones were prepared by polycondensation of a metal chloride and an acetylene monomer in the presence of Cul. Platinum and palladium... 

Transition metal poly-ynes have large third-order optical susceptibilities (X ) which consist of contributions from the real and imaginary parts of the third-order hyperpolarizabilities (y and y", respectively). In previous studies, various optical measurements were used to determine the nonlinear hyper-polarizabilities of the polymers.Most recently, an extensive study of the structural dependence of the hyperpolarizabilities of the platinum and palladium... 

Porter, P.L., Guha, S., Kang, K. and Frazier, C.C., "Structural dependence of platinum and palladium poly-ynes on third-order nonlinearity," Polymer 32 1756 (1991). 

Fig. 7. Comparison of experimental phase boundary concentrations between the isotropic and biphasic regions for various liquid-crystalline polymer solutions with the scaled particle theory for wormlike hard spherocylinders. ( ) schizophyllan water [65] (A) poly y-benzyl L-glutamate) (PBLG)-dimethylformamide (DMF) [66-69] (A) PBLG-m-cresoI [70] ( ) PBLG-dioxane [71] (O) PBLG-methylene chloride [71] (o) po y(n-hexyl isocyanate) (PHICH°Iuene at 10,25,30,40 °C [64] (O) PHIC-dichloromethane (DCM) at 20 °C [64] (5) a po y(yne)-platinum polymer (PYPt)-tuchIoroethane (TCE) [33] ( ) (hydroxypropyl)-cellulose (HPC)-water [34] ( ) HPC-dimethylacetamide (DMAc) [34] (N) (acetoxypropyl) cellulose (APC)-dibutylphthalate (DBP) [35] ( ) cellulose triacetate (CTA)-trifluoroacetic acid [72]...

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