Digital Alchemy Applied to Molecular Dynamics

Recently, colloidal and nanoparticle synthesis techniques have grown in scope more quickly than the capacity to populate relevant phase diagrams, challenging the predictive ability of computer simulation. Meeting this challenge suggests the development of new techniques that simultaneously explore the dynamics of particles’ canonical degrees of freedom, and particle attributes. Here, we describe a Molecular Dynamics implementation of the “Digital Alchemy” framework. This framework extends statistical ensembles to include variation in “alchemical” degrees of freedom describing particle attributes. We apply alchemical Molecular Dynamics simulations to particles interacting via a Lennard-Jones-Gauss potential, and show that several previously known crystal structures, including a quasicrystal, exhibit stable behavior in this alchemically extended design space, allowing for optimization and exploration.