Resolving the atomic structure of supported nanometer-size Au clusters

Field-ion microscopy (FIM) is used to resolve the atomic structure and orientation of individual nanometer-size Au clusters supported on sharp tips of W, Pt, and a Pt/Ir alloy. The FIM images from a single cluster illustrate that the technique is capable of providing atomically resolved images of supported nanometer-size clusters in an ultrahigh vacuum environment. By comparing computer simulations of a FIM image to experimental data, the atomic structure and orientation of the supported cluster can be determined.