A model is developed for describing phason defects in quasicrystals in
the form of dilation filaments. This model is used to calculate the e
nergy of edge dislocations in quasicrystals including the interaction
of this type of dislocation with its ''intrinsic'' phason defects and
with the equilibrium phason defects present in a quasicrystal. It is s
hown that the contribution of ''intrinsic'' phason defects to the tota
l energy of an edge dislocation in a quasicrystal is substantial. (C)
1997 American Institute of Physics.