Expansions of the interatomic potential for different boundary conditions and the transition to the thermodynamic limit

Maksim D. Tomchenko

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arXiv · 1403.8014

Expansions of the interatomic potential for different boundary conditions and the transition to the thermodynamic limit

Maksim D. Tomchenko

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Abstract

We analyze the possible expansions of the interatomic potential $U(|\textbf{r}_{1}-\textbf{r}_{2}|)$ in a Fourier series for a cyclic system and a system with boundaries. We also study the transition from exact expansions for a finite system to the expansion that is commonly used in the thermodynamic limit. The analysis shows that such a transition distorts the potential of a bounded system by making it cyclic.

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Maksim D. Tomchenko. 2014-03-31. Expansions of the interatomic potential for different boundary conditions and the transition to the thermodynamic limit. https://arxiv.org/abs/1403.8014

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