Nanoindentation of a supported Au cluster

Abstract

An atomic force microscope has been used in the attractive (noncontact) force mode to image individual nanometer-size Au clusters preformed in the gas phase and deposited on a variety of atomically flat substrates. Using this technique, it is possible to reliably image preformed clusters in their as-deposited positions. This capability allows nanoindentation studies to measure the mechanical properties of individual nanometer-size clusters supported on atomically flat substrates. We find that the elastic modulus of a 3.1-nm Au cluster is 56-19+33 GPa. This should be compared to a bulk value of 80 GPa for polycrystalline Au and 120 GPa for crystalline Au in the [111] direction.