Thermodensity coupling in phase-field-crystal-type models for the study of rapid crystallization

We self-consistently derive a formalism that couples a phase field crystal (PFC) density field to thermal transport. It yields a theory for nonuniform transient temperature and density evolution, and includes local latent heat release during atomic rearrangements of the PFC density field. The basic formalism is applied to the original PFC model, demonstrating its capacity to capture heat transfer and recalescence in solidification. With an aim towards consistently incorporating temperature and other thermodynamic variables into PFC modeling, a new classical density field theory for solid/liquid/vapor systems is then derived. It presents a different approach to those used in the PFC literature while retaining the major advantages that have become the hallmark of PFC modeling; the new model is also based entirely on physical density, temperature, and pressure scales. We end the paper by applying the thermal-density coupling formalism to this new multiphase density functional theory/PFC model.