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arXiv · 1301.2142

Screened empirical bond-order potentials for Si-C

Lars Pastewka·Andreas Klemenz·Peter Gumbsch·Michael Moseler
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Abstract

Typical empirical bond-order potentials are short ranged and give ductile instead of brittle behavior for materials such as crystalline silicon or diamond. Screening functions can be used to increase the range of these potentials. We outline a general procedure to combine screening functions with bond-order potentials that does not require to refit any of the potential's properties. We use this approach to modify Tersoff's [Phys. Rev. B 39, 5566 (1989)], Erhart & Albe's [Phys. Rev. B 71, 35211 (2005)] and Kumagai et al.'s [Comp. Mater. Sci. 39, 457 (2007)] Si, C and Si-C potentials. The resulting potential formulations correctly reproduce brittle materials response, and give an improved description of amorphous phases.

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Lars Pastewka, Andreas Klemenz, Peter Gumbsch, Michael Moseler. 2013-01-10. Screened empirical bond-order potentials for Si-C. https://doi.org/10.1103/physrevb.87.205410

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