Molecular dynamics simulations were performed to calculate the structure of a Na-borosilicate glass. The topography of an initial flat surface of this glass caused by the instantaneous release of atoms weakly bonded to the silicate network was studied, giving the minimum roughness of the surface. The resulting profiles were compared to experimental data obtained by atom probe tomography on a complex nuclear glass, after having verified that simulations are valid for the complex glass. As experimental profiles are much thicker, these comparisons support the concept that interdiffusion is a key mechanism controlling the long-term corrosion rate of nuclear glasses. (C) 2013 Elsevier B.V. All rights reserved.