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arXiv · 1705.01751

Polytypism in the ground state structure of the Lennard-Jonesium

Lívia B. Pártay·Christoph Ortner·Albert P. Bartók·Chris J. Pickard·Gábor Csányi
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Abstract

We present a systematic study of the stability of nineteen different periodic structures using the finite range Lennard-Jones potential model discussing the effects of pressure, potential truncation, cutoff distance and Lennard-Jones exponents. The structures considered are the hexagonal close packed (hcp), face centred cubic (fcc) and seventeen other polytype stacking sequences, such as dhcp and $9R$. We found that at certain pressure and cutoff distance values, neither fcc nor hcp is the ground state structure as previously documented, but different polytypic sequences. This behaviour shows a strong dependence on the way the tail of the potential is truncated.

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Lívia B. Pártay, Christoph Ortner, Albert P. Bartók, Chris J. Pickard, Gábor Csányi. 2017-05-04. Polytypism in the ground state structure of the Lennard-Jonesium. https://doi.org/10.1039/c7cp02923c

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