We perform molecular dynamic simulations of liquid nanoparticles deposited on a disordered substrate. The motion of the nanoparticle is characterized by a “stick and roll” diffusive process. Long simulation times $(\simeq \mu \mathrm{s})$, analysis of mean square displacements and stacking time distribution functions demonstrate that the nanoparticle undergoes a normal diffusion in spite of long sticking times. We propose a phenomenological model for the size and temperature dependence of the diffusion coefficient in which the activation energy scales as $N^{1∕3}$.

• Received 17 March 2004

DOI:https://doi.org/10.1103/PhysRevB.70.115402