We report evidence in this letter for the encapsulation of Fe clusters
supported by single crystal TiO2. After thermal annealing in ultrahig
h vacuum (UHV) at 500-700-degrees-C for several hours, Fe clusters are
almost completely covered by Ti suboxides TiO(x) while Fe remains mai
nly in the metallic state. The phenomenon can be clearly measured usin
g LEIS (low energy ion scattering) and XPS (X-ray photoelectron spectr
oscopy).