  We discuss various approaches to modeling the interatomic interactions for
molecular dynamics with special focus on the geometrical structural properties.
The type of interactions considered are so called reactive force fields, i.e.
interactions without predefined bonds and structures. The discussed cases cover
the well known Stillinger-Weber, Tersoff-Brenner, EDIP, ReaxFF and ABOP
interaction models as well as some additional examples. We discuss also a
recently published synthesis of diamond-like structures by isotropic pair
potential with multiple minima and use this concepts to propose a sort of
classification scheme for interactions with respect to the geometry modeling.
In most details we discuss the Tersoff-Brenner potentials and also
Stillinger-Weber potential, since these models still appear quite popular in
recent research, even though the newer models are more efficient in most
respects, except of simplicity. We also propose simple modifications of the
basically three-body interactions in order to attempt the simulation of
four-body correlation effects. The main motive for this study has been to find
how the geometrical features are related to theoretical concepts and whether
all possibilities for simplification are exhausted.
