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The controlled pyrolysis of transition metal cluster substituted metal carboxylates, e.g., M4O[(CO)9Co3CCO2]6, where M = Co and Zn, and M'2(CO)9Co3CCOO4, where M' = Co, Mo, and Cu, results in the formation of high surface area, amorphous solids that are active and selective catalysts for the hydrogenation of crotonaldehyde. In contrast to conventional metal catalysts that are selective for the double bond hydrogenation, these new solids exhibit high regioselectivities for the conversion of crotonaldehyde (2-butenal) to crotyl alcohol (2-butenol). Further, the observed selectivities depend on the metal cluster carboxylate structure.

Complex cobalt-carbonyl ligand based clusters of clusters are used as molecular precursors for self-supported model catalysts. These precursors consist of two metal layers: an outer of the complex Co-carbonyl ligands, and a core of metal (e.g. Co or Zn) carboxylate groups. Partial thermolysis at low temperature (LT) of these materials under hydrogen results in almost completely decarbonylated material with a mainly unchanged carboxylate metal core. Complete pyrolysis at higher temperatures (HT) in hydrogen leads to mixed metal environment. These materials were used as a heterogenous catalyst in the gas phase hydrogenation of crotonaldehyde. The maximum yield of 27 % of desired product crotyl alcohol was observed when HT-CoCo was used as the catalyst at 423 K. The catalyst activity and the crotyl alcohol selectivity remained unchanged over 2 days of operation. The bimetallic ZnCo catalysts showed lower selectivity to crotyl alcohol than the CoCo catalysts.

The discrete molecular clusters of clusters, M1140[(CO)9Co3CCO2]6, M = Co, Zn undergo thermolysis with the production of highly porous solid materials. Evaluation of the catalytic properties of these materials has been investigated using the hydrogenation of 1,3- butadiene as a test reaction. These experiments suggest it is the unique structure of the porous materials that is responsible for the high activities and the selectivities observed.

The ferraborane HFe4 (CO)12 BH2 sublimes at 50 °C and decomposes by loss of H2 and CO on various substrate surfaces at 160–180 °C to yield films having metallic appearances with typical thicknesses of 4000Å. These films are amorphous by X-ray, conduct electricity and adhere well to glass, metal and silicon substrates. The composition was determined by ESCA and Auger spectroscopies. The films exhibit highly uniform composition and the Fe/B ratio is 4 showing that film stoichiometry is defined by the cluster core. The ESCA chemical shifts show the presence of boride and metallic iron. At present the bulk film contains a high level of oxygen in the form of iron and boron oxides. No ax-iron is present by X-ray or Mössbauer spectroscopies. Some carbon and hydrogen (SIMS) are present. Mössbauer spectra show the presence of magnetic iron similar to that exhibited by authentic Fe80 B20 samples but the films also contain substantial paramagnetic iron.