An Investigation of Surface Energy of Gold Nanoparticles; Molecular Dynamic Study

Surface energy of Gold nanoparticles (1-6 nm) was studied by using molecular dynamic simulation. The kinetic, potential, total energy and the number of neighbouring atoms from center to surface were investigated to obtain more details. According to our results potential energy in the particles were controlled by numbers of neighbouring atoms. Unlike what has been thought, surface energy is not restricted to surface monolayer and it is extended within nanoparticles. In fact surface energy has layer-by-layer effect (surface effect). Consequently, in nano-scale, we may reach the particles which all atoms are only affected by surface effect with decreasing of the size of the particles .It will be forecast that the nanoparticles have a critical size; particles smaller than critical size are fully affected by surface effect and there will be no bulk materials, so that the structure of nanoparticles can be divided into two regions; bulk zone and surface zone. But when the sizes of the particles become smaller than critical size the structure of nanoparticles should be considered as one region (surface zone).

کلیدواژه ها:

Surface energy ، Molecular Dynamic simulation ، Gold Nanoparticles