Inverse Design of Pressure-Induced Solid—Solid Transitions in Colloids Using the Alchemical Ensemble*

Recent developments in anisotropic particle synthesis have shown promise for using these particles as building blocks for functional materials. However, due to the large design spaces that are available to us, it can be challenging to find appropriate building blocks for target behaviors. Here, instead of mapping out the phase behavior for a range of particle shapes, we present a new, alternative computational statistical mechanical approach that couples together multiple systems within the “alchemical ensemble” — a generalized, statistical mechanical framework in which model attributes are allowed to fluctuate along with thermodynamic variables. The alchemical ensemble has application to a wide variety of design problems within statistical mechanics. Here, we demonstrate its use in the design of particle shapes for target materials properties, and present examples of candidate colloidal- and nano-particles designed within the alchemical ensemble specifically for structurally reconfigurable colloidal crystals.