Molecular dynamics simulations of amorphous silica surface properties with truncated Coulomb interactions

•Energies of silica clusters are calculated for Wolf shifted BKS potential.•The use of the Wolf shifted BKS potential for amorphous silica surfaces is validated.•Large volumes of silica aerogel can be simulated using MD simulations.

Molecular Dynamics simulations have been performed to evaluate the capacity of the van Beest, Kramer and van Santen (BKS) [1] potential with truncated Coulomb interactions as proposed by A. Carré et al. [2] to reproduce amorphous silica surface properties. We compare the results obtained with the truncated BKS potential with those obtained from its full-range interaction version. Energies of (SiO2)n clusters are computed for both potentials. The energies and structural properties of small aggregates of silica (from ≈ 3.5 nm to 7.6 nm of diameter) are investigated at high temperature. Both potentials lead to the same results for those properties when considering the transition from the core to the shell of aggregates. The significant computation time saved with this cut-off on Coulomb interactions allows for large-scale simulations of silica aerogels.