Investigation into the formation of 13-6 helical multi-shell gold nanowires

Accelerated molecular dynamics (AMD) is employed to investigate the phase transformation of a gold nanowire from a face-center cubic (FCC) structure to a helical multi-shell (HMS) structure at room temperature. The obtained phase structures of 13-6 HMS and superhelical multi-shell (sHMS) gold nanowires are demonstrated; however, the probabilities of forming such two configurations are close because there is only a very small difference in their cohesive energies. Moreover, density functional theory (DFT) is utilized to prove the existence of the 13-6 sHMS and HMS nanowires. The structures from AMD and DFT are analyzed by radius distribution and angular correlation functions. Finally, tension and compression loading are performed to understand the mechanical property, with results revealing that the helical angle of the gold nanowires has a significant effect on tensile loading but not on compression loading.