  Motivated by recent research of Nikitin et al. (J.Phys.D vol. 49,
055301(2009)), we examine the effects of interatomic interactions on adatom
surface diffusion. By using a mean-field approach in the random walk problem,
we derive a nonlinear diffusion equation and analyze its solutions. The results
of our analysis are in good agreement with direct numerical simulations of the
corresponding discrete model. It is shown that by analyzing a time dependence
of adatom concentration profiles one can estimate the type and strength of
interatomic interactions.
