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Title: Liquidlike Behavior of Supercritical Fluids

Abstract

The high frequency dynamics of fluid oxygen has been investigated by inelastic x-ray scattering, at high pressures and room temperature. In spite of the markedly supercritical conditions (T{approx_equal}2T{sub c}, P>10{sup 2}P{sub c}), the sound velocity exceeds the hydrodynamic value of about 20%, a feature which is the fingerprint of liquidlike dynamics. The comparison of the present results with literature data obtained in several fluids allow us to identify the extrapolation of the liquid-vapor-coexistence line in the (P/P{sub c}, T/T{sub c}) plane as the relevant edge between liquidlike and gaslike dynamics. More interestingly, this extrapolation is very close to the non-metal-metal transition in hot dense fluids, at pressure and temperature values as obtained by shock wave experiments. This result points to the existence of a connection between structural modifications and transport properties in dense fluids.

Authors:
;  [1];  [2];  [1];  [3];  [4];  [2]
  1. Research Center SOFT-INFM-CNR, Universita di Roma 'La Sapienza', I-00185, Rome (Italy)
  2. (Italy)
  3. European Synchrotron Radiation Facility, BP 220, 38043 Grenoble (France)
  4. Dipartimento di Fisica, Universita di Roma 'La Sapienza', 00185 Rome (Italy)
Publication Date:
OSTI Identifier:
20861486
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 97; Journal Issue: 24; Other Information: DOI: 10.1103/PhysRevLett.97.245702; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; EXTRAPOLATION; LIQUIDS; OXYGEN; SHOCK WAVES; SOUND WAVES; TEMPERATURE RANGE 0273-0400 K; VAPORS; VELOCITY; X-RAY DIFFRACTION

Citation Formats

Gorelli, F., Santoro, M., LENS, Via N. Carrara 1, I-50019 Sesto Fiorentino, Florence, Scopigno, T., Krisch, M., Ruocco, G., and Research Center SOFT-INFM-CNR, Universita di Roma 'La Sapienza', I-00185, Rome. Liquidlike Behavior of Supercritical Fluids. United States: N. p., 2006. Web. doi:10.1103/PHYSREVLETT.97.245702.
Gorelli, F., Santoro, M., LENS, Via N. Carrara 1, I-50019 Sesto Fiorentino, Florence, Scopigno, T., Krisch, M., Ruocco, G., & Research Center SOFT-INFM-CNR, Universita di Roma 'La Sapienza', I-00185, Rome. Liquidlike Behavior of Supercritical Fluids. United States. doi:10.1103/PHYSREVLETT.97.245702.
Gorelli, F., Santoro, M., LENS, Via N. Carrara 1, I-50019 Sesto Fiorentino, Florence, Scopigno, T., Krisch, M., Ruocco, G., and Research Center SOFT-INFM-CNR, Universita di Roma 'La Sapienza', I-00185, Rome. Fri . "Liquidlike Behavior of Supercritical Fluids". United States. doi:10.1103/PHYSREVLETT.97.245702.
@article{osti_20861486,
title = {Liquidlike Behavior of Supercritical Fluids},
author = {Gorelli, F. and Santoro, M. and LENS, Via N. Carrara 1, I-50019 Sesto Fiorentino, Florence and Scopigno, T. and Krisch, M. and Ruocco, G. and Research Center SOFT-INFM-CNR, Universita di Roma 'La Sapienza', I-00185, Rome},
abstractNote = {The high frequency dynamics of fluid oxygen has been investigated by inelastic x-ray scattering, at high pressures and room temperature. In spite of the markedly supercritical conditions (T{approx_equal}2T{sub c}, P>10{sup 2}P{sub c}), the sound velocity exceeds the hydrodynamic value of about 20%, a feature which is the fingerprint of liquidlike dynamics. The comparison of the present results with literature data obtained in several fluids allow us to identify the extrapolation of the liquid-vapor-coexistence line in the (P/P{sub c}, T/T{sub c}) plane as the relevant edge between liquidlike and gaslike dynamics. More interestingly, this extrapolation is very close to the non-metal-metal transition in hot dense fluids, at pressure and temperature values as obtained by shock wave experiments. This result points to the existence of a connection between structural modifications and transport properties in dense fluids.},
doi = {10.1103/PHYSREVLETT.97.245702},
journal = {Physical Review Letters},
number = 24,
volume = 97,
place = {United States},
year = {Fri Dec 15 00:00:00 EST 2006},
month = {Fri Dec 15 00:00:00 EST 2006}
}
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