  This work addresses differences in predicted elastic fields created by
dislocations either by the Phase Field Crystal (PFC) model, or by static Field
Dislocation Mechanics (FDM). The PFC order parameter describes the topological
content of the lattice, but it fails to correctly capture the elastic
distortion. In contrast, static FDM correctly captures the latter but requires
input about defect cores. The case of a dislocation dipole in two dimensional,
isotropic, elastic medium is studied, and a weak coupling is introduced between
the two models. The PFC model produces compact and stable dislocation cores,
free of any singularity, i.e., diffuse. The PFC predicted dislocation density
field (a measure of the topological defect content) is used as the source
(input) for the static FDM problem. This coupling allows a critical analysis of
the relative role played by configurational (from PFC) and elastic (from static
FDM) fields in the theory, and of the consequences of the lack of elastic
relaxation in the diffusive evolution of the PFC order parameter.
