Graphical abstractHighlights► Combined X-ray and light scattering study was performed on ZnS nanoparticles. ► Ligands with different steric properties, dodecyl- and oleylamine, are compared. ► Nanoparticles exhibit sizes of 3–5 nm. ► Thickness of the ligand shell is about 1.9 nm.

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Ring-opening metathesis polymerization was used to synthesize amphiphilic, phosphorescent block copolymers that self-assemble into nanometer-scaled aggregates when dissolved in a selective solvent. The triblock random copolymer architecture is built up by using an oligoglycol-substituted norbornene derivative for the hydrophilic part, 2,3-norbornenedicarboxylic acid dimethyl ester, as the first segment of the hydrophobic part and a statistical segment made using norbornene-functionalized dyes as the second segment of the hydrophobic part. The dyes comprise a blue fluorescent carbazole derivative serving as the host and a red phosphorescent platinum complex serving as the guest material. Emission properties of the amphiphilic triblock random copolymer dissolved in a nonselective solvent are exclusively determined by the host material. Only blue emission of the carbazole-derivative can be observed. When the polymer is dissolved in a selective solvent, polymer aggregates are formed and energy transfer occurs. In this case, deep red phosphorescence stemming from the platinum complex used as guest component can be observed. The amphiphilic triblock random copolymer architecture allows for the dispersion of the platinum chromophore in a solvent in which the parent chromophore is insoluble, the realization of a large Stokes shift of about 260 nm and significant suppression of platinum complex self-quenching, resulting in considerable phosphorescent quantum yields. Absorbance, luminescence, quantum yield, and lifetime measurements of this polymer and several model polymers in selective and unselective solvents as well as in the solid state have been performed to understand the energy transfer from the host to the guest dye in this particular system.

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2008 Carbazole derivatives R 0150Synthesis and Photophysical Properties of 3,6-Diphenyl-9-hexyl-9H-carbazole Derivatives Bearing Electron-Withdrawing Groups. -Suzuki cross-coupling reaction of carbazole (I) with boronic acid derivatives (II) yields the title compounds (III) which exhibit pronounced red shifts of their absorption and emission properties compared to their parent compound (I). Formyl derivative (IIIb) shows particularly interesting photophysical properties; its capability to act as the emissive layer in organic light-emitting diodes is confirmed. Reduction of the two aldehyde functionalities in (IIIb) leads to hydroxymethyl derivative (IV) possessing low thermal stability, thus disqualifying (IV) for the envisaged application as emissive layer. -(KREMSER, G.; HOFMANN, O. T.; SAX, S.; KAPPAUN, S.; LIST, E. J. W.; ZOJER, E.; SLUGOVC*, C.; Monatsh. Chem. 139 (2008) 3, 223-231; Inst. Chem. Technol. Inorg. Mater., Karl Franzens Univ. Graz, A-8010 Graz, Austria; Eng.) -H. Hoennerscheid 21-121