  We present a simple view on band unfolding of the energy bands obtained from
supercell calculations. It relies on the relationship between the local density
of states in reciprocal space (qLDOS) and the fully unfolded band structure.
This provides an intuitive and valid approach not only for periodic, but also
for systems with no translational symmetry. By refolding into the primitive
Brillouin zone of the pristine crystal we recover the conventional unfolded
bands. We implement our algorithm in the SIESTA package and apply it to defects
on Si and graphene.
