Novel mixed ligand sandwich complexes: competitive binding of iron with benzene, coronene, and C-60

Organometallic complexes of iron with benzene, coronene and C-60 are produc ed in a molecular beam and studied with time-of-flight mass spectrometry an d laser photodissociation. The cation complexes are produced in a pulsed no zzle laser vaporization source using an iron rod coated with a sublimed fil m of coronene and/or C-60. Benzene is seeded in the expansion gas. Masses o f the form [A(x)-Fe-B-y](+) are observed when A and B are benzene, coronene , or C-60, taken any two at a time. Masses are observed for all combination s where x + y = 1 or 2, indicating the formation of monoligand and sandwich complexes. Mixed-Ligand sandwiches form with comparable abundance to homol igand sandwiches. Mass-selected photodissociation probes the relative bondi ng strengths in these new species. (C) 1999 Elsevier Science B.V.