Wetting-to-Nonwetting Transition in Metal-CoatedC60

Based on ab initio and density-functional theory calculations, an empirical potential is proposed to model the interaction between a fullerene molecule and many sodium atoms. This model predicts homogeneous coverage of ${\mathrm{C}}_{60}$ below eight Na atoms and a progressive droplet formation above this size. The effects of ionization, temperature, and external electric field indicate that the various, and apparently contradictory, experimental results can indeed be put into agreement.