Diagnostic Structures for Interatomic Potentials

Abstract

unrelaxed structures are easily reproducible, enabling them to be used by other authors to readily test potential formalisms other than those considered in this work. Specifically, we will perform our calculations on unrelaxed bcc � -iron (ferrite) with interstitial carbon. This will enable us to make a contribution to the ongoing debate as to how the ferritic phase of steel might be best represented using a semi-empirical potential. 3–6) This is an important topic because many properties of steel originate from the interaction of carbon (and nitrogen) with point and extended defects. These interactions must be treated using a semiempirical or empirical approach, since the numbers of atoms involved in such interactions place them well out of reach of current ab-initio methods such as density functional theory (DFT). 7,8)