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arXiv · 0807.1339

Compressibility of solid helium

Carlos P. Herrero
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Abstract

The compressibility of solid helium (3He and 4He) in the hcp and fcc phases has been studied by path-integral Monte Carlo. Simulations were carried out in both canonical (NVT) and isothermal-isobaric (NPT) ensembles at temperatures between 10 and 300 K, showing consistent results in both ensembles. For pressures between 4 and 10 GPa, the bulk modulus B is found to decrease by about 10 %, when temperature increases from the low-temperature limit to the melting temperature. The isotopic effect on the bulk modulus of helium crystals has been quantified in a wide range of parameters. At 25 K and pressures on the order of 1 GPa, the relative difference between 3He and 4He amounts to about 2 %. The thermal expansion has been also quantified from results obtained in both NPT and NVT simulations.

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Carlos P. Herrero. 2008-07-09. Compressibility of solid helium. https://doi.org/10.1088/0953-8984%2F20%2F29%2F295230

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