  The self-assembled monolayers of alkane thiolates on Ag (111) surfaces and
nanoparticles are studied using molecular dynamics. Reactive force fields allow
simulations of very large systems such as nanoparticles of 10 nm. Stable
(sqrt(7) X sqrt(7))R19.1{\deg} assemblies are obtained as experimentally
observed for these systems. Only nanoparticles smaller than 4 nm show a
spontaneous restructuration of the metallic core. The preferred adsorption site
is found to be in an on-top position, in good agreement with recent X-ray
absorption near edge structure experiments. Moreover, similar distances between
the sulfur headgroups are found on the facets and edges.
