Posted by iacovecr on Monday, October 31, 2011 in Recent Publications.

Citation:

French WR, Iacovella CR, Cummings PT, (2011) The Influence of Molecular Adsorption on Elongating Gold Nanowires, Journal of Physical Chemistry C, 115 pp 18422–18433

DOI:10.1021/jp203837r
arXiv:1108.6251v1

Abstract:

Using molecular dynamics simulations, we study the impact of physisorbing adsorbates on the structural and mechanical evolution of gold nanowires (AuNWs) undergoing elongation. We used various adsorbate models in our simulations, with each model giving rise to a different surface coverage and mobility of the adsorbed phase. We find that the local structure and mobility of the adsorbed phase remain relatively uniform across all segments of an elongating AuNW, except for the thinning region of the wire where the high mobility of Au atoms disrupts the monolayer structure, giving rise to higher solvent mobility. We analyzed the AuNW trajectories by measuring the ductile elongation of the wires and detecting the presence of characteristic structural motifs that appeared during elongation. Our findings indicate that adsorbates facilitate the formation of high-energy structural motifs and lead to significantly higher ductile elongations. In particular, our simulations result in a large number of monatomic chains and helical structures possessing mechanical stability in excess of what we observe in vacuum. Conversely, we find that a molecular species that interacts weakly (i.e., does not adsorb) with AuNWs worsens the mechanical stability of monatomic chains.

Tags: Elongation, Gold, Nanowire, Propane, TB-SMA