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Register a new userTwo stage order-disorder transformation in simple monatomic supercritical fluid: superstable tetrahedral local order
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Added by
Nikolai M. Chtchelkatchev
Publication date
2013
fields
Physics
and research's language is
English
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The local order units of dense simple liquid are typically three dimensional (close packed) clusters: hcp, fcc and icosahedrons. We show that the fluid demonstrates the superstable tetrahedral local order up to temperatures several orders of magnitude higher than the melting temperature and down to critical density. While the solid-like local order (hcp, fcc) disappears in the fluid at much lower temperatures and far above critical density. We conclude that the supercritical fluid shows the temperature (density) driven two stage melting of the three dimensional local order. We also find that the structure relaxation times in the supercritical fluid are much larger than ones estimated for weakly interactive gas even far above the melting line.
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