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The use of alternative nitrogen sources for growing GaN materials by organometallic vapor phase epitaxy (OMVPE) is being continuously investigated in the hope of achieving device-quality films under moderate conditions, in comparison to conventional methods. Employing the single molecule precursor (N 3 ) 2 Ga[(CH 2 ) 3 NMe 2 ], and using a cold-wall CVD reactor, epitaxial films of GaN, transparent in appearance and stoichiometric in composition, were deposited on c-plane sapphire, in the absence of ammonia, above 1073 K, under low pressures (between 0.080 and 100.0 mbar). Dense, amorphous, and very smooth films were grown at temperatures as low as 773 K. The influence of substrate temperature, reactor pressure, and the effect of small quantities of additional ammonia, on the growth rate and the film properties, were studied in some detail. The films were characterized by high-resolution X-ray diffraction (XRD) (e.g., full width at half maximum (FWHM) of the 0002 GaN rocking curve of 130 arcsec), X-ray reflectometry, scanning electron microscopy (SEM), atomic force microscopy (AFM) (root mean square roughness of 1.9 nm), X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), Rutherford backscattering (RBS) (Ga/N = 1:1 ± 0.05), and photoluminescence (PL) measurements (band edge luminescence at 3.45 eV and FWHM of 0.22 eV at 300 K).

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Consecutive vaporization cycles for the preparation of heterogeneous catalysts: Active Cu‐ and ZnO‐containing methanol‐synthesis catalysts were obtained by vaporizing suitable organometallic precursors into mesoporous silicates, followed by thermal treatment (see scheme). The catalytically active components in the final material have nanoscopic dimensions. The methanol production by the catalysts is similar to that of systems synthesized by the classical route.

A monomeric titanium complex suitable for liquid‐injection MOCVD applications is synthesized and its molecular structure is determined by single‐crystal X‐ray diffraction. [Ti(OiPr)2‐(tbaoac)2] (see Figure), (tbaoac) = tertiarybutylacetoacetonate), is a volatile alkoxide‐(beta)diketonate precursor that has a low melting point and very good solubility in common organic solvents.

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The adsorption and subsequent reactions of 2,5-dimercapto-1,3,4-thiadiazole (DMcT) and 2-mercapto-5-methyl-1,3,4-thiadiazole (McMT) on polycrystalline gold films have been characterized by X-ray photoelectron spectroscopy, X-ray absorption spectroscopy, IR spectroscopy, mass spectrometry, and scanning tunneling microscopy. Adsorption from solution was studied as well as vapor deposition under ultrahigh vacuum conditions. McMT adsorbs from an ethanolic solution to Au surfaces but decomposes to a large extent to give nonstoichiometric, nitrogen-deficient thin films containing smaller fragments, whereas DMcT forms thin films on Au surfaces consisting of intact molecules and oligomers resulting from surface polymerization. A temperature-dependent XPS study shows that McMT forms a thin film of intact molecules after deposition from the vapor phase at a substrate temperature of 130 K, which decomposes above 300 K to yield new, stable surface species.

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