Failure modes in polymorphic multicomponent solid growth

Polymorphic materials are ubiquitous in complex systems exhibiting mesoscale order, from organic crystals to biomolecular condensates. A unique feature of these systems is the possibility of assembling a particular polymorph, or phase, out of many possibilities at the same thermodynamic state. However, this process depends on kinetic factors that are poorly understood. In this study, we predict a new failure mode for the growth of polymorphic materials in systems with many components, in which dynamical coexistence occurs between ordered and disordered assembly trajectories. We then show that this dynamical phase transition is preceded by the formation of a disordered wetting layer in simulations of multicomponent crystal growth. The broad applicability of our model suggests that this dynamical phase transition may occur in a variety of polymorphic materials.