We briefly reviewed the fully EAM-Atomistic model, the volume-based
EAM-QCL, the reconstruction based EAM-QCL and their corresponding
EAM-QNLs.  We study the sharp stability estimations of all the models.
We find a critical condition for the stability analysis and conclude
that the sharp stability condition of the volume based EAM-QNL is
always close to that of the fully atomistic model as long as  the
atomistic region is sufficiently large and  the continuum region is
nontrivial.