  We propose to parametrize the Stillinger-Weber potential for covalent
materials starting from the valence force field model. All geometrical
parameters in the Stillinger-Weber potential are determined analytically
according to the equilibrium condition for each individual potential term,
while the energy parameters are derived from the valence force field model.
This parametrization approach transfers the accuracy of the valence force field
model to the Stillinger-Weber potential. Furthermore, the resulting
Stilliinger-Weber potential supports for stable molecular dynamics simulations,
as each potential term is at energy minimum state separately at the equilibrium
configuration. We employ this procedure to parametrize Stillinger-Weber
potentials for the single-layer MoS2 and black phosphorous. The obtained
Stillinger-Weber potentials predict accurate phonon spectrum and mechanical
behaviors. We also provide input scripts of these Stillinger-Weber potentials
used by publicly available simulation packages including GULP and LAMMPS.
