Photoluminescence high solid-state

Dibenzophosphole A was in fact the first type of phosphole to be prepared [9], but it has only very recently been used as a building block for the preparation of jr-conjugated systems. In this regard, polymer 70 is obtained with a high polydis-persity (Mn = 5 X 102 Mw = 6.2 X 103) by Ni-catalyzed homo-coupling of derivative 69 (Scheme 4.20) [52]. The presence of o3-P centers, which are potential donor sites for the Ni catalyst, does not prevent C-C bond formation. This macromolecule is photoluminescent in the solid state (2em = 516 nm), a property of potential interest for the development of OLEDs [52]. 

The nonlinear absorption of Ptn acetylide chromophores has also continued to retain the interest of many researchers. Malmstrom and coworkers have recently investigated Pt-acetylide chromophores blended with solid-state polymer matrices [94], An example of such a complex is 4.7. They found that the photoluminescence properties of the blends agreed well with that of dilute THF solutions containing the Pt-acetylides. Optical power limiting experiments showed that the clamping levels for dyes nonbonded to the polymer host were about half that for dyes in the highly cross-linked solids at similar concentrations. 

Crystalline and amorphous silicons, which are currently investigated in the field of solid-state physics, are still considered as unrelated to polysilanes and related macromolecules, which are studied in the field of organosilicon chemistry. A new idea proposed in this chapter is that these materials are related and can be understood in terms of the dimensional hierarchy of silicon-backbone materials. The electronic structures of one-dimensional polymers (polysilanes) are discussed. The effects of side groups and conformations were calculated theoretically and are discussed in the light of such experimental data as UV absorption, photoluminescence, and UV photospectroscopy (UPS) measurements. Finally, future directions in the development of silicon-based polymers are indicated on the basis of some novel efforts to extend silicon-based polymers to high-dimensional polymers, one-dimensional superlattices, and metallic polymers with alternating double bonds. 

Fig. 8 Two terfluorenes with very high photoluminescent quantum yields in the solid state...

This rigid core compound displayed a PLQY value in the microciystalline powder of q = 48% (Barbarella et al., 2001). DTTOMe4 belongs to a class of oligothiophene-S,S-dioxides characterized by high photoluminescence efficiency both in solution and in the solid state, contrary to conventional thiophene oligomers and conformationally flexible oligothiophene-... 

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