Why I do atomistic simulations

Abstract In this perspective, I discuss why I do atomistic simulations. Atomistic simulations have now been a key component of materials science research for the better part of a century. They provide a direct window into the individual motion of atoms, revealing dynamical behavior that is impossible to see any other way. The level of detail is immense. However, not all of that detail can matter at the meso- and macroscale where engineering models perform quite well in describing materials. In my view, the thrill of discovery, of seeing something unexpected for the first time, is one of the key reasons for performing atomistic simulations. And, while many novel results may not immediately translate to engineering-level models, in many cases they reveal new possibilities that change how we think about a problem. The novel and unexpected behavior revealed by these simulations are particularly important when considering materials out of equilibrium, where kinetic processes dictate the historical evolution of the material.