Formation energies and concentrations of microclusters for homogeneous nucleation

The Gibbs free formation energies and the energies of formation for argon clusters having 3–19 atoms have been computed. These calculations have been carried out for the free cluster (atomistic) model and the model of interacting monomers and clusters (IMC). In the IMC model the interactions among background monomers and monomer–cluster interactions are considered. However, for the results presented in this work, only the effect of the interactions among background monomers has been computed. Comparison of the free cluster model with the IMC model indicates that even for argon the interactions among background monomers should not be ignored. The results of both models become almost identical at high temperatures. The depletion of monomers has also been considered. A simple relation is given which describes how background monomers are depleted in a supercooled system. The depletion of background monomers can easily be incorporated into the rate of nucleation and, when performed, this introduces a temperature-dependent correction to the nucleation rate.