Formation of a new class of layered, microcrystalline polymers from a simple hydrolytic polycondensation of n-alkyltrichlorosilanes in water is demonstrated. The structure of the polymeric condensate, determined from a combination of spectroscopic, diffraction, and thermal analysis techniques, consists of highly uniform, pillared microcrystallites in which the inorganic siloxy backbones are present in periodic layers, each containing a monomolecular layer of intercalated water, separated by crystalline assemblies of alkyl chains. The alkyl-chain organization shows a remarkable resemblance to that in highly organized, self-assembled monolayers formed from the precursor silane molecules on hydrophilic substrates and this parallel lends support to the critical importance of water in monolayer self-assembly of silanes.

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Self-assembled thin films of layered copper alkanediylbis-(phosphonates) retain the amine-specific intercalation chemistry of the corresponding microcrystalline solids. Aliphatic and aromatic amines bind in a 1:1 ratio to coordinatively unsaturated copper ions in anhydrous Cu 2 (O 3 P(CH 2 ) 8 PO 3 ); and by selecting an amine with an appropriate functional tail group, a chemically and sterically well-defined interlamellar binding site for CO 2 is created. Powder X-ray diffraction, Fourier transform infrared spectroscopy, and solid-state NMR experiments were used to study the intercalation of 3-aminopropanol, (3-aminopropyl)methyldihydroxysilane, and p-xylylenediamine, and their reversible reaction with CO 2 to form carbonates and carbamates, respectively. By growing these films on the electrodes of a quartz crystal microbalance device, a sensor can be fabricated for monitoring CO 2 in gas streams at concentrations of 0.5-19% (v/v). A Henrian response (frequency change directly proportional to CO 2 partial pressure) was observed, and the time required for equilibration of these devices with CO 2 , using 5-layer films, was 3-4 min. Effective diffusion coefficients for CO 2 in the films were determined using a dualtransport model and were found to be in the range (6-9) × 10 -9 cm 2 /s.

It was found that oxalic acid is one of the main products in the Briggs-Rauscher oscillating reaction. In nonoscillating solutions, oxidation of iodomalonic acid and/or diiodomalonic acid by Fenton-type reactions also produced oxalic acid as well as I(2). Mesoxalic acid yielded oxalic acid under similar conditions. Tartronic acid was nearly inert to Fenton-type reactions; however, tartronic acid was oxidized by iodate and iodine to mesoxalic acid, which in turn could form oxalic acid in the presence of H(2)O(2) plus catalyst. Iodotartronic acid appeared to be a short-lived but significant intermediate, thus both tartronic acid and mesoxalic acid are possible intermediates. Glycolic acid and glyoxylic acid are not intermediates in the oxidation of iodomalonic acid, since they in turn produce formic acid under similar nonoscillating conditions.

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