title: Thermal stabilization of thin gold nanowires by surfactant-coating: a molecular dynamics study.
abstract: The thermal stabilization of thin gold nanowires with a diameter of about 2 nm by surfactants is investigated by means of classical molecular dynamics simulations. While the well-known melting point depression leads to a much lower melting of gold nanowires compared to bulk gold, coating the nanowires with surfactants can reverse this, given that the attractive interaction between surfactant molecules and gold atoms lies beyond a certain threshold. It is found that the melting process of coated nanowires is dominated by surface instability patterns, whereas the melting behaviour of gold nanowires in a vacuum is dominated by the greater mobility of atoms with lower coordination numbers that are located at edges and corners. The suppression of the melting by surfactants is explained by the isotropic pressure acting on the gold surface (due to the attractive interaction) which successfully suppresses large-amplitude thermal motions of the gold atoms.
authors.affiliation: Institute of Ion Physics and Applied Physics, University of Innsbruck, Technikerstrasse 25, 6020, Innsbruck, Austria. s.huber@uibk.ac.at
authors.forename: Stefan E
authors.initials: SE
authors.lastname: Huber
authors.forename: Chompunuch
authors.initials: C
authors.lastname: Warakulwit
authors.forename: Jumras
authors.initials: J
authors.lastname: Limtrakul
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Tsukuda
authors.forename: Michael
authors.initials: M
authors.lastname: Probst
mesh_terms: D000327:Adsorption; D003198:Computer Simulation; D006046:Gold / Q000737:chemistry*; D008956:Models, Chemical; D008958:Models, Molecular; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D013501:Surface-Active Agents / Q000737:chemistry*; D013696:Temperature
chemical_list: D013501:Surface-Active Agents; D006046:Gold