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Collective dynamics in liquid lead: Generalized propagating excitations

Taras Bryk* and Ihor Mryglod

  • Institute for Condensed Matter Physics, National Academy of Sciences of Ukraine, 1 Svientsitskii Street, UA-79011 Lviv, Ukraine

  • *Present address: Department of Chemistry, University of Houston, Houston, TX 77004.
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Phys. Rev. E 63, 051202 – Published 10 April, 2001

DOI: https://doi.org/10.1103/PhysRevE.63.051202

Abstract

A microscopic approach to the investigation of generalized collective excitations, developed recently for pure liquids, is applied to the study of the spectrum of collective excitations in a liquid metal. The calculations are performed for liquid lead at two temperatures (above the melting point and in high-temperature region) and the results are compared. From the analysis of spectra, obtained for different basis sets of dynamical variables, we conclude that there exist three branches of propagating collective excitations, which correspond to sound and heat (high- and low-frequency) waves in the liquid. It is shown that the branch of low-frequency heat waves contains a propagation gap in the hydrodynamic region. An analytical expression for the width of the propagation gap for low-frequency heat waves is derived.

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Phys. Rev. E 63, 051202– Published 10 April, 2001
  • Received 20 October 2000

© 2001 American Physical Society

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