Molecular Dynamics Study of Alkanethiolate Self-Assembled Monolayer coated Gold Nanoparticle

Through molecular simulations we have observed that the surface of gold nanoparticles become highly corrugated by the adsorption of alkanethiolate self-assembled monolayers (SAMs). Furthermore, as the temperature is increased, the SAMs dissolve into the gold nanoparticle, creating a liquid mixture at temperatures much lower than the melting temperature of the gold nanoparticle. By analyzing the mechanical and chemical properties of gold nanoparticles at temperatures below the melting point of gold, with different SAM chain lengths and surface coverage properties, we have determined that the system is metastable. The model and computational results that provide support for this hypothesis are presented in this paper.