Ligand Structure and Free Energy of Nanoparticles on Substrates*

2D nanoparticle superlattices are commonly assembled on or transferred to solid substrate supports such as silicon wafers, silica, or graphene. In order to better understand nanoparticles in this context, molecular dynamics simulations were carried out to study the nanoparticle-substrate interactions. Simulations were run using HOODLT/HOOMD-blue to analyze the capping ligand vortices and adhesion free energies of substrate supported gold nanoparticles of various sizes grafted with hydrocarbons of various lengths. The relation of this work to nanoparticle superlattices is also discussed.