Stochastic analysis of movements on surfaces: The case of C60 on Au(111)

Molecular dynamics simulations of C-60 on Au(1 1 1) reveal that the molecular diffusion consists of random sequences of stick, slide, and stick and slip periods. Stochastic analysis of forty trajectories shows that initially C-60 follows a superdiffusive-sub-ballistic-like motion, which then turns into super-diffusive. Individual trajectories present a variety of diffusive motions that even include subdiffusion. The analysis of the displacement moments indicates Fractional Brownian motion (FBM), as underlying stochastic mechanism, a finding further supported by the analysis of the velocity correlation function. (C) 2015 Elsevier B.V. All rights reserved.