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Title: Medium-Range Fluctuations Accompanying the Metal-Nonmetal Transition in Expanded Fluid Hg

Abstract

We have carried out small angle x-ray scattering experiments of expanded fluid Hg in the metal-nonmetal (M-NM) transition region around 9.0 g cm{sup -3}. Increase of small angle scattering intensity following the Ornstein-Zernike equation is clearly observed in the M-NM transition region as well as near the liquid-vapor critical point at 5.8 g cm{sup -3}. The short-range correlation length, R, becomes twice as large in the M-NM transition region as in the critical region. The enhancement of R in expanded fluid Hg suggests a new type of fluctuations reflecting a first-order M-NM transition.

Authors:
 [1]; ;  [2];  [3];  [4]
  1. Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima 739-8521 (Japan)
  2. Graduate School of Engineering, Kyoto University, Kyoto 606-8501 (Japan)
  3. SPring-8/RIKEN 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148 (Japan)
  4. SPring-8/JASRI 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan)
Publication Date:
OSTI Identifier:
20951345
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 18; Other Information: DOI: 10.1103/PhysRevLett.98.185504; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CORRELATIONS; EQUATIONS; FLUCTUATIONS; LIQUIDS; METALS; NONMETALS; SMALL ANGLE SCATTERING; VAPORS; X-RAY DIFFRACTION

Citation Formats

Inui, M., Matsuda, K., Tamura, K., Ishikawa, D., and Ohishi, Y. Medium-Range Fluctuations Accompanying the Metal-Nonmetal Transition in Expanded Fluid Hg. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.185504.
Inui, M., Matsuda, K., Tamura, K., Ishikawa, D., & Ohishi, Y. Medium-Range Fluctuations Accompanying the Metal-Nonmetal Transition in Expanded Fluid Hg. United States. doi:10.1103/PHYSREVLETT.98.185504.
Inui, M., Matsuda, K., Tamura, K., Ishikawa, D., and Ohishi, Y. Fri . "Medium-Range Fluctuations Accompanying the Metal-Nonmetal Transition in Expanded Fluid Hg". United States. doi:10.1103/PHYSREVLETT.98.185504.
@article{osti_20951345,
title = {Medium-Range Fluctuations Accompanying the Metal-Nonmetal Transition in Expanded Fluid Hg},
author = {Inui, M. and Matsuda, K. and Tamura, K. and Ishikawa, D. and Ohishi, Y.},
abstractNote = {We have carried out small angle x-ray scattering experiments of expanded fluid Hg in the metal-nonmetal (M-NM) transition region around 9.0 g cm{sup -3}. Increase of small angle scattering intensity following the Ornstein-Zernike equation is clearly observed in the M-NM transition region as well as near the liquid-vapor critical point at 5.8 g cm{sup -3}. The short-range correlation length, R, becomes twice as large in the M-NM transition region as in the critical region. The enhancement of R in expanded fluid Hg suggests a new type of fluctuations reflecting a first-order M-NM transition.},
doi = {10.1103/PHYSREVLETT.98.185504},
journal = {Physical Review Letters},
number = 18,
volume = 98,
place = {United States},
year = {Fri May 04 00:00:00 EDT 2007},
month = {Fri May 04 00:00:00 EDT 2007}
}
  • We have performed direct measurements and quantum molecular-dynamics simulations for expanded aluminum at densities two to nine times lower than the normal solid density and internal energies ranging from 7 to 70 kJ/g. The simulation results were found to be in good agreement with the experimental data and reproduce well the main trends observed in the measured dependencies of the electrical resistivity and pressure versus internal energy along isochores. A systematic study of the optical conductivity spectra, one-particle density of states, and the distributions of the electronic charge over supercell shows that the transition of expanded aluminum to a nonmetallicmore » state takes place close to the density at which the constant volume derivative of the electrical resistivity on internal energy becomes negative.« less
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  • No abstract prepared.