Reactive interatomic potentials and their geometrical features

Ladislav Kocbach; Suhail Lubbad

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arXiv · 0908.1540

Reactive interatomic potentials and their geometrical features

Ladislav Kocbach·Suhail Lubbad

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Abstract

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.

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Ladislav Kocbach, Suhail Lubbad. 2009-10-19. Reactive interatomic potentials and their geometrical features. https://arxiv.org/abs/0908.1540

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