  In this paper the the effect of Dzyaloshinskii-Moriya interaction and
anisotropy on the Entanglement of Heisenberg chain has been studied. While the
anisotropy suppress the entanglement due to favoring of the alignment of spins,
the DM interaction restores the spoiled entanglement via creation of the
quantum fluctuations. Thermodynamic limit of the model and emerging of
non-analytic behavior of the entanglement have also been probed. The
singularities of the entanglement correspond to the critical boundary
separating different phases of the model. The singularity of the entanglement
derivative approaches the critical point from the gapped phase and will be
symmetric if both phase on the boundary are gapped.
