Issue
Europhys. Lett.
Volume 76, Number 4, November 2006
Page(s) 623 - 629
Section Condensed matter: structural, mechanical and thermal properties
DOI http://dx.doi.org/10.1209/epl/i2006-10322-3
Published online 18 October 2006
Europhys. Lett., 76 (4), pp. 623-629 (2006)
DOI: 10.1209/epl/i2006-10322-3

Influence of boundaries on high-pressure melting experiments

V. Sorkin, E. Polturak and J. Adler

Physics Department, Technion-Israel Institute of Technology - Haifa, 32000 Israel


received 22 June 2006; accepted in final form 25 September 2006
published online 18 October 2006

Abstract
At low pressure, free surfaces play a crucial role in the melting transition, but to maintain pressure, the sample surface must be acted upon by some pressure-transmitting medium. To examine the effect of this medium on melting, we performed Monte Carlo simulations of a system of argon atoms in the form of a slab with upper and lower boundaries. We examined two cases: one with a soft and the other with a rigid medium at the boundaries. We found that in the presence of a rigid medium, melting resembles the mechanical lattice instability found in a surface-free solid. With a soft medium at the boundary, melting begins at the surface and at a lower temperature. The relevance of these results to experiment is discussed.

PACS
64.70.Dv - Solid-liquid transitions.
62.50.+p - High-pressure and shock wave effects in solids and liquids.
82.20.Wt - Computational modeling; simulation.

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