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The reaction of LiBH(C 2 H 5 ) 3 with Os 3 (CO) 12 or Ir 4 (CO) 12 leads to the formation of spectroscopically detectable formyl complexes. In the latter case, the complex is smoothly converted to [Ir 4 (CO) 11 H] − , an expected decompositioFn complex of the corresponding polynuclear formyl complex, [Ir 4 (CO) 11 CHO] − .

The reactions of LiHB(C2H5)3 and LiDB(C2H5)3 with Re2(CO)10, Ir4(CO)12, Os3(CO)12, Ru3(CO)12 and Rh4(CO)12 have been studied by 1H, 2H and 13C NMR techniques. Results suggest the formation of formaldehyde and methanol in these systems, as well as the existence of previously unreported formyl complexes. A 2H isotope effect is noted in the apparent increase in stability of cluster formyl complexes.

The reaction of acetic [13C]formic anhydride with sodiumpentacarbonylmanganate proceeds rapidly at 0°C to give 13CO substituted pentacarbonylmanganese hydride as the predominant product. The results are consistent with the formation of a short-lived neutral formyl complex, (CO)5Mn13CHO.

Homogeneous catalysis by transition metal clusters is attracting increasing attention, (1,3) as well as the modeling of some heterogeneous catalysts by these complexes. (4) Cluster catalysis in homogeneous systems has been reported for some technologically relevant reactions such as hydr formylat ion, (5) water-shift, (6) oxidation (7) and Fisher-Tropsch. (8) In addition, rhodium carbonyl clusters are present during the catalytic synthesis of alcohols from carbon monoxide and hydrogen.(9)

Photoelectron spectroscopy of adsorbed Xe (PAX) was used to characterize various Pt/TiO2 (100) surfaces on an atomic scale. The PAX data provide useful information on both geometrical and electronic states of various surface sites. For example, both Ar ion sputtering and high temperature annealing (850 °C) in vacuum produce a distribution of (high charge density) surface defect sites, most likely Ti3+ and Ti2+, whose local surface potentials are higher than on a stoichiometric TiO2 surface by 0.5 and 1 eV, respectively. Submonolayer deposits of Pt on a stoichiometric TiO2 exhibits much lower local surface potentials (0.5–1 eV) than sputter‐roughened bulk Pt, suggesting modified charge densities at these sites.