Direct Wolf summation of a polarizable force field for silica

Abstract

We extend the Wolf direct, pairwise r −1 summation method with spherical truncation to dipolar interactions in silica. The Tangney-Scandolo interatomic force field for silica takes regard of polarizable oxygen atoms whose dipole moments are determined by iteration to a self-consistent solution. With Wolf summation, the computational effort scales linearly in the system size and can easily be distributed among many processors, thus making large-scale simulations of dipoles possible. The details of the implementation are explained. The approach is validated by estimations of the error term and simulations of microstructural and thermodynamic properties of silica.

The Wolf method applied to the type I methane and carbon dioxide gas hydrates

“…This method takes the summation of the Coulomb interactions entirely in the reciprocal space [78] causing the computational cost to scale as O(N 2 ) [77,[102][103][104] and, as it was noted previously, this is the main downside of the method.…”

“…Since this equation only requires evaluating of a pairwise sum truncated in an appropriate distance, the computational cost scales linearly with increasing system size (N), i.e., it is of order O(N) [42,62,70,82,85,93,104].…”

Simulation of crack propagation in alumina with ab initio based polarizable force field

“…This means that for small magnitudes of the wave vectors k, the charge structure factor is also small. In previous studies 16,23 it was shown that the reciprocal-space term is indeed negligible compared to the real-space part, provided that the splitting parameter κ is chosen small enough. As however a smaller κ results in a larger real-space cutoff r c , the latter has to be chosen three or four times the size of a typical shortrange cutoff radius in metals.…”

Ab initio parametrized polarizable force field for rutile-type SnO2

“…The term describing the electrostatic contribution to the total energy of the system consists of charge-charge, charge-dipole and dipole-dipole contributions. The Wolf summation was used for calculation of Coulomb interactions, (described in detail in [18,19]), with a cutoff of 13 Å . It was found that an Ewald parameter of j = 0.1 was sufficient.…”