Computer simulations of the condensation of nanoparticles from the gas phase

The crystallization of Ni nanoclusters from the gas phase is investigated with the help of molecular dynamics simulations using empirical tight-binding potentials. In these simulations, the condensation of hot liquid droplets from the gas phase is observed which later crystallize and agglomerate. It is shown that agglomeration of crystallized particles is the dominating growth mode and that the shapes of the final particles are similar to the shapes of experimentally grown Ni nanoparticles. In the second part, the evolution of the structure and the morphology of an agglomerated particle during sintering at 600 and 900K is studied. While in both cases the original disordered interface between the agglomerated particles vanishes, the shapes of the resulting particles differ considerably due to the different surface diffusion rates.