Title: Migration barriers for surface diffusion on a rigid lattice: challenges and solutions,
Abstract: Atomistic rigid lattice Kinetic Monte Carlo is an efficient method for
simulating nano-objects and surfaces at timescales much longer than those
accessible by molecular dynamics. A laborious part of constructing any Kinetic
Monte Carlo model is, however, to calculate all migration barriers that are
needed to give the probabilities for any atom jump event to occur in the
simulations. One of the common methods of barrier calculations is Nudged
Elastic Band. The number of barriers needed to fully describe simulated systems
is typically between hundreds of thousands and millions. Calculations of such a
large number of barriers of various processes is far from trivial. In this
paper, we will discuss the challenges arising during barriers calculations on a
surface and present a systematic and reliable tethering force approach to
construct a rigid lattice barrier parameterization of face-centred and
body-centred cubic metal lattices. We have produced several different barrier
sets for Cu and for Fe that can be used for KMC simulations of processes on
arbitrarily rough surfaces. The sets are published as Data in Brief articles
and available for the use.