Direct Synthesis of Metal Cluster Complexes by Deposition of Mass-Selected Clusters with Ligand: Iron with CO

A new technique for preparing metal cluster complexes of a desired nuclearity by co-depositing ligand with metal clusters mass-selected from a cluster beam is illustrated by the deposition of Fe, Fe2, and Fe3 with excess CO. The matrices formed were studied by Fourier transform infrared spectroscopy. Unexpectedly, deposition of Fe2 produced the CO-unbridged Fe2(CO)8 isomer, known primarily from matrix photochemistry, rather than the well-known diiron nonacarbonyl.