  The physical and chemical properties of metal nanoparticles differ
significantly from those of free metal atoms as well as from the properties of
bulk metals, and therefore, they may be viewed as a transition regime between
the two physical states. Within this nanosize regime, there is a wide
fluctuation of properties, particularly chemical reactivity, as a function of
the size, geometry, and electronic state of the metal nanoparticles. In recent
years, great advancements have been made in the attempts to control and
manipulate the growth of metal particles to pre-specified dimensions. One of
the main synthetic methods utilized in this endeavor, is the capping of the
growing clusters with a variety of molecules, e.g. polymers. In this paper we
attempt to model such a process and show the relationship between the
concentration of the polymer present in the system and the final metal particle
size obtained. The theoretical behavior which we obtained is compared with
experimental results for the cobalt-polystyrene system.
