  The phase field crystal (PFC) method has emerged as a promising technique for
modeling materials with atomistic resolution on mesoscopic time scales. The
approach is numerically much more efficient than classical density functional
theory (CDFT), but its single mode free energy functional only leads to
lattices with triangular (2D) or BCC (3D) symmetries. By returning to a closer
approximation of the CDFT free energy functional, we develop a systematic
construction of two-particle direct correlation functions that allow the study
of a broad class of crystalline structures. This construction examines planar
spacings, lattice symmetries, planar atomic densities and the atomic
vibrational amplitude in the unit cell of the lattice and also provides control
parameters for temperature and anisotropic surface energies. The power of this
new approach is demonstrated by two examples of structural phase
transformations.
