X-ray photoemission and absorption spectroscopy of supported nanoscale iron clusters

Fe particles with sizes in the range 1-5 nm, formed by a gas-aggregation method and deposited onto graphite and C-60 supports, were studied by x-ray photoemission spectroscopy, x-ray absorption spectroscopy, and magnetic linear dichroism. Clusters deposited onto a C-60 coated graphite substrate become embedded within the fullerene film, and have an increased resistance to oxidation compared to exposed clusters supported on a graphite surface. No evidence for hybridization between the electronic states of Fe and C-60 is seen. The magnetic dichroism signal of the exposed clusters increases sharply with the film thickness because of the increased cluster interactions. (C) 1999 American Institute of Physics. [S0021-8979(99)05717-5].