  A scanning tunneling microscope (STM) supplemented with a force sensor is
used to study the mechanical properties of a novel metallic nanostructure: a
freely suspended chain of single gold atoms. We find that the bond strength of
the nanowire is about twice that of a bulk metallic bond. We perform ab initio
calculations of the force at chain fracture and compare quantitatively with
experimental measurements. The observed mechanical failure and nanoelastic
processes involved during atomic wire fabrication are investigated using
molecular dynamics (MD) simulations, and we find that the total effective
stiffness of the nanostructure is strongly affected by the detailed local
atomic arrangement at the chain bases.
