A new method is presented for analyzing the effects of self-absorption on photoluminescence integrating sphere quantum yield measurements. Both the observed quantum yield and luminescence spectrum are used to determine the self-absorption probability, taking into account both the initial emission and subsequent absorption and reemission processes. The analysis is experimentally validated using the model system of the laser dye perylene red dispersed in a polymer film. This approach represents an improvement over previous methods that tend to overestimate the true quantum yield, especially in cases with high sample absorbance or quantum yield values.

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A scalable synthesis of the "flat" tridecameric inorganic cluster [Al(13)(μ(3)-OH)(6)(μ-OH)(18)(H(2)O)(24)](15+) has been realized by treating an aqueous aluminum nitrate solution with a zinc-metal powder at room temperature. Single crystals and polycrystalline samples are readily obtained in yields exceeding 55% relative to the starting reagent Al(NO(3))(3). Products have been characterized by X-ray diffraction and solid-state (27)Al MAS and MQMAS NMR.

We report here on the polymerization of epoxide monomers on incipient aluminum nanoparticle cores and the effects of changing the epoxide-capping precursor and the metallic monomer ratio on the resultant stability and particle size of passivated and capped aluminum nanoparticles. When altering the ratio of aluminum to cap monomer precursor, nanoparticles capped with epoxydodecane, epoxyhexane, and epoxyisobutane show a clear decreasing trend in stability with decreasing alkane substituent length. The nanoparticle core size was unaffected by cap ratio or composition. PXRD (powder X-ray diffraction) and DSC/TGA (differential scanning calorimetry/thermal gravimetric analysis) confirm the presence of successfully passivated face-centered cubic (fcc) aluminum nanoparticles. We also report preliminary results from ATR-FTIR (attenuated total reflectance-Fourier transform infrared), (13)C CPMAS (cross-polarization/magic-angle spinning), and (27)Al MAS solid-state NMR (nuclear magnetic resonance) measurements. The most stable aluminum nanoparticle-polyether core-shell nanoparticles are found at an Al:monomer mole ratio of 10:1 with an active Al(0) content of 94%.

Synthesis of the Hydroxide Cluster [Al 13 (μ 3 -OH) 6 (μ-OH) 18 (H 2 O) 24 ] 15+ from anAqueous Solution. -[Al13(μ3-OH)6(μ-OH)18(H2O)24](NO3)15 is synthesized by treatment of an aqueous solution of Al(NO3)3 with Zn metal powder (Al:Zn = 2:1) at room temperature (55% yield). The single crystal XRD results are in agreement with those reported previously [see CI 2008-17-015]. The synthesis is scalable to produce large quantities of the compound, which is useful as a precursor to solution-processed Al 2 O 3 and related thin films for electronics. -(WANG, W.; WENTZ, K. M.; HAYES, S. E.; JOHNSON, D. W.; KESZLER*, D. A.; Inorg. Chem. 50 (2011) 11, 4683-4685, http://dx.doi.org/10.1021/ic200483q ; Dep. Chem., Oreg. State Univ., Corvallis, OR 97331, USA; Eng.) -W. Pewestorf 32-009