X-ray photoelectron spectroscopy of low surface concentration mass-selected Ag clusters

We have developed an experimental setup for the study of small mass-selected clusters delivered by soft landing to a model oxide support. An automated deposition system to achieve accurately quantified homogeneous surfaces is described which also overcomes beam instability. Finally we present some recent photoelectron spectroscopic data from the analysis of mass-selected Ag-n(+) clusters deposited on a Xe covered Al2O3 surface. Large core-level binding energy shifts are observed as a function of deposited cluster size and diffusion/agglomeration within the noble gas layer. (C) 2000 American Institute of Physics. [S0021-9606(00)70544-7].