Preparation, structure, and a coarse-grained molecular dynamics model for dodecanethiol-stabilized gold nanoparticles

Thiol-stabilized metal nanoparticles possess unique properties in the comparison with larger-scale materials, which enable their use in many promising chemical and biological applications. We have synthesized thiol-coated colloidal gold nanoparticles (AuNP) soluble in non-polar organic solvents by a simplified procedure, in which AuCl 4 - was initially reduced in aqueous phase and then coated with thiol residues and transferred to organic phase. Using the transmission electron micrograph (TEM) imaging, the average diameter of a dodecanethiol-stabilized AuNP was estimated to be 3.75 ± 0.06 nm. Based on the experimental TEM data, a new coarse-grained molecular dynamics model of AuNP was developed. The model was applied for studying self-assembly of AuNPs on a flat graphite surface, enabling further elucidating the structure and packing of the ligand shell around the spherical nanoparticle core.