Accelerated molecular dynamics simulation of thin-film growth with the bond-boost method

Abstract

We review the bond-boost method for accelerated molecular dynamics (MD) simulation and we demonstrate its application to kinetic phenomena relevant to thin-film growth. To illustrate various aspects of the method, three case studies are presented. We first illustrate aspects of the bond-boost method in studies of the diffusion of Cu atoms on Cu(001). In these studies, Cu interactions are described using a semi-empirical embedded-atom method potential. We recently extended the bond-boost method to perform accelerated ab initio MD (AIMD) simulations and we present results from preliminary studies in which we applied the bond-boost method in AIMD to uncover diffusion mechanisms of Al adatoms on Al(110). Finally, a problem inherent to many rare-event simulation methods is the 'small-barrier problem', in which the system resides in a group of states connected by small energy barriers and separated from the rest of phase space by large barriers. We developed the state-bridging bond-boost method to address this problem and we discuss its application for studying the diffusion of Co clusters on Cu(001). We discuss the outlook for future applications of the bond-boost method in materials simulation.