Electronic Structure and Ordering

How to take into account local concentration in Ising-based Monte-Carlo: illustration with zirconium hydrides

“…To sum up, the main interest of this work is to give a ready-to-use Monte-Carlo methodology for treating local concentration, which can be applied for any alloy or intermetallic whose ordering energy is described by an Ising model with strongly concentration-dependent pairwise interactions (which is often the case for substitutional binary alloys [13], for instance). The path can be also enlarged for more complex interatomic potentials.…”

“…This question of taking or not local concentration dependency to reproduce the correct thermodynamics, is all the more important that in the case of Ising models, concen-tration dependency of pairwise interactions can sometimes be quite strong, with sign changes [13]. Furthermore, using clustering developments Gonis et al [14] have demonstrated that concentration-independent interactions are rigorously valid only for strictly finite systems, such as a nanoparticle, whereas treatment of infinite systems, such as bulk alloys, requires an explicit concentration dependency of interactions.…”