On the Lifetime of Suspended Atomic Chains Formed from Stretched Metallic Gold Nanowires

Abstract

number of atoms as a function of tem- perature. We have carried out classical molecular dynamics simulations using tight-binding models with a second moment approximations. Our results suggest a more complex phenomenon than pre- viously anticipated. The dynamics of chain rupture seems to be determined beyond thermodynamics contributions and the bond breaking patterns were observed to be chain-length dependent. these systems; continuous, mixed models with empiri- cal potentials, and even ab initio ones. In this work we have theoretically investigated the lifetime of suspended atomic chains (LACs) formed from stretched gold NWs. Experimental LAC formation involves stochastic aspects which implies the need of considering many cases at dif- ferent conditions (temperature, pulling velocities, crys- tallographic orientations, etc.). The large number of cases and size of the structures (hundreds of atoms) pre- cludes the use of full ab initio methods due to the high computational cost. A natural choice to study these sys- tems could be to use embedded atom potential (EAM) (31, 32) or tight-binding model with second moment ap- proximations (TB-SMA) (33, 34). EAM and TB-SMA have good records of well describing metallic structures. Our choice was to use TB-SMA by the reasons detailed in the methodology section.