Stillinger-Weber potential
The Stillinger-Weber potential is a classic physical potential for the representation of special crystal lattices . The main area of application is the simulation of the lattice dynamics of silicon and silicon-like elements and their alloys with one another.
As with all classical potentials, no statement can be made about quantum mechanical effects. Nevertheless, they are useful when considering systems that consist of many atoms or molecules and the quantum mechanical aspect takes a back seat. The advantage over other potentials, such as the Lennard-Jones potential or the Tersoff potential, is the good ratio of accuracy to computational effort.
The accuracy relates to silicon and similar semiconductors crystallizing in the diamond lattice and arises from the formulation of the potential, which prefers a tetrahedral base. At the same time, however, this is also a disadvantage, since other configurations that can arise, for example, under pressure, as well as effects on surfaces and interfaces are not reproduced realistically. Due to the moderate computational effort involved in simulating the lattice forces, it is still worth using it for large, possibly periodic structures in which many time steps are to be simulated. With a modern computer cluster, a system with up to a million atoms and several million time steps can be examined within a few days.
literature
F. Stillinger and TA Weber, Phys. Rev. B 31, 5262 (1985).