Thin film evolution: Dewetting dynamics of a bimodal molecular system

Deposition of submonolayer coverages of 3,4,9,10-perylenetetracarboxylic diimide onto NaCl(001) results in the bimodal growth of coexisting square and needle-shaped islands. The epitaxy of each island type was determined from molecular and atomic resolution noncontact atomic force microscopy images. Postdeposition, the needle islands grow while the square islands disappear completely within days. This is characterized as a dewetting transition, the dynamics of which has been described and empirically fit to the monomolecular growth model, a model typically applied to biological growth.