SUBNANOMETER NICKEL CLUSTERS IN COMPLEX REDUCING AGENTS

Nickel-based, complex reducing agent (NiCRA) prepared by reacting Ni(O Ac)(2), NaH and t-BuONa in THF were studied by transmission electron m icroscopy. Nickel is in the form of 1 nm-large clusters. In presence o f bipyridyl ligands particles as small as 0.5 nm are detected. The for mation and stability of nickel clusters is attributed to the strong re ducing potential of the NaH-t-BuONa mixture complexing the nickel clus ters. Bipyridyl ligands exert an additional stabilization so that clus ters containing less than 10 atoms could be present.