Water-soluble poly(ferrocenylsilane) (PFS) and poly(styrenesulfonate) (PSS) of alternating charge are shown to self-assemble in a layer-by-layer fashion on primed Au, Si, and quartz substrates to create the first examples of organic−organometallic electrostatic superlattices from polymers with ferrocene units in the backbone. The layer-by-layer assembly of these electrostatic superlattices has been monitored through frequency changes with layer deposition using a quartz-crystal microbalance (QCM), a regular film thickness increase observed using ellipsometry, and step-wise absorbance increases observed using ultraviolet−visible (UV−vis) spectroscopy. As well, structural information was obtained using X-ray photoelectron spectroscopy (XPS), water contact angle measurements, and atomic force microscopy (AFM). These superlattices are of interest as possible precursors to patterned magnetic and redox active multilayers.

Direct visualization of organometallic-organic and novel all-organometallic multilayer superlattices prepared by layer-by-layer assembly of cationic/anionic polyferrocenylsilane and anionic polystyrene sulfonate polyelectrolytes using a gold coating/transmission electron microscopy (TEM) technique is reported.

The preparation, characterization, properties, and reactivity of a novel quantum-confined CdS nanocluster containing a chemically active aniline surface are described, along with three general methods for the covalent attachment of a wide scope of molecular moieties to the cluster surface. The formation of facile covalent linkages via DCC mediated amidization, secondary amine formation, and thiourea condensation is discussed and, as the introduction of surface functionality is crucial for the eventual realization of molecular electronic devices fabricated from such nanoclusters, several derivatized nanoclusters bearing interesting chromophoric, fluorescent, electroactive, and chiroptical tethered species are described. All three derivatization techniques occur under very mild conditions that have been demonstrated not to disturb the integrity of the nanocluster core.Key words: quantum dot, nanocluster, semiconductor, surface-functionalized, nanostructured.

The photoinduced decomposition of dimethylformamide suspensions of 10 different surfacesubstituted thiolate-capped 30 Å cadmium sulfide quantum-confined nanoclusters was studied. HPLC analysis demonstrates that decomposition proceeds at a constant rate and produces only precipitated cluster aggregates and the symmetric disulfide corresponding to the thiolate cap as the only organic product. The dependence of the disulfide photogeneration kinetics on the Hammett σ p parameter for the remote substituent indicates that both electron donors and acceptors enhance the rate and is mimicked by nanocluster fluorescence quenching efficiencies of the substituents, suggesting a photodecomposition mechanism involving facile electronic communication between the quantum dot core and the remote substituent. Further evidence for the mechanism was obtained from the product distribution ratios of the photodecomposition of a 4-nitrothiolate/4-methylthiolate-mixed surface nanocluster.

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