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Among the synthesized (CH3)2AlOR compounds (R=CH2CH2OCH3 (1), CH(CH3)CH2OCH3 (2), CH2CH2OCH(CH3)2 (3), CH(CH3)CH2OC(CH3)3 (4)), 2 and 4 have been characterized by 1H and 27Al NMR spectroscopy and X-ray diffraction, while 1, 2 and 3 have been analysed by mass spectrometric measurements with a mass spectrometer equipped with a special designed input system imitating a CVD reactor. While in the solid state it is unequivocally clear that the compounds are present in the form of an oxygen-bridged dimer with a five-coordinated aluminum center, in solution an equilibrium exists between two fluxional species containing tetra and penta coordinated Al atoms respectively.

Here we investigate Cr2O3 chromia film deposition via metalorganic chemical vapour deposition (MOCVD) on Fe-Cr-Ni AISI304 stainless steel (Cr18.2, Ni 9.07, Mn 1.73, Si 0.6, C 0.0022 wt%). For characterization purposes films were deposited also on (001) silicon wafers. Chromia film growth was compared for three different precursors: (1) Cr(CO)6, (2) Cr(III)hexafluoro-acetyl-acetonate and (3) tris (2,2,6,6-tetramethyl-3,5-heptane-ditionatohromium (III). The morphological, structural and chemical properties of the films were compared. The most useful precursor was found to be Cr(CO)6 and the films obtained with this precursor were further investigated by scratch testing and nonoindentation to determine the film adhesion and coating hardness.

A series of new bis(indenyl)zirconium diaryloxides of general formula Ind2Zr(OL)2 (L = C6H5, C6F5, 2,6-Me2C6H3, 2,4,6Me3C6H2, 4-tBUC6H4, were synthesized by a metathesis reaction of Ind2ZrC12 with the appropriate thallium aryloxide salt, Tl0L. The complexes were characterized by 1H and 13C NMR techniques. They were also examined as catalysts for ethene and 1-hexene polymerization with methylalumoxane as co-catalyst, and a trend of the polymerization activity as a funetion of aryloxide ligands was observed. An interpretation of this trend, considering both the electronic and steric effects of the substituents on the aryloxide rings, was proposed.