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Phase diagram of silicon from atomistic simulations

M. Kaczmarski·O. N. Bedoya-Martinez·E. R. Hernandez
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Abstract

In this letter we present a calculation of the temperature-pressure phase diagram of Si in a range of pressures covering from -5 to 20 GPa and temperatures up to the melting point. The phase boundaries and triple points between the diamond, liquid, $β$-Sn and ${Si}_{34}$ clathrate phases are reported. We have employed efficient simulation techniques to calculate free energies and to numerically integrate the Clausius-Clapeyron equation, combined with a tight binding model capable of an accuracy comparable to that of first-principles methods. The resulting phase diagram agrees well with the available experimental data.

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M. Kaczmarski, O. N. Bedoya-Martinez, E. R. Hernandez. 2005-02-25. Phase diagram of silicon from atomistic simulations. https://doi.org/10.1103/physrevlett.94.095701

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