  We apply the phase field crystal model to study the structure and energy of
symmetric tilt grain boundaries of bcc iron in 3D. The parameters for the model
are obtained by using a recently developed eight-order fitting scheme [A.
Jaatinen et al., Phys. Rev. B 80, 031602 (2009)]. The grain boundary free
energies we obtain from the model are in good agreement with previous results
from molecular dynamics simulations and experiments.
