Relations between the longitudinal and transverse sound velocities in strongly coupled Yukawa fluids

The Journal of Chemical Physics

Kryuchkov

et al. 2019

Self Cite

A simple practical approach to describe transverse (shear) waves in strongly-coupled Yukawa fluids is presented. Theoretical dispersion curves, based on hydrodynamic consideration, are shown to compare favorably with existing numerical results for plasma-related systems in the long-wavelength regime. The existence of a minimum wave number below which shear waves cannot propagate and its magnitude are properly accounted in the approach. The relevance of the approach beyond plasma-related Yukawa fluids is demonstrated by using experimental data on transverse excitations in liquid metals Fe, Cu, and Zn, obtained from inelastic x-ray scattering. Some potentially important relations, scalings, and quasi-universalities are discussed. The results should be interesting for a broad community in chemical physics, materials physics, physics of fluids and glassy state, complex (dusty) plasmas, and soft matter.

Section: Application To Liquid Metalsmentioning

confidence: 72%

Onset of transverse (shear) waves in strongly-coupled Yukawa fluids

The Journal of Chemical Physics

Kryuchkov

et al. 2019

Self Cite

“…The instantaneous sound velocity c ∞ appears to be rather close to the conventional thermodynamic (adiabatic) sound velocity c s [40,41] for soft Yukawa systems considered here. This has been recently documented [38]. Moreover, for such soft interactions the strong inequality c L ≫ c T normally holds, which implies c L ≃ c ∞ ≃ c s .…”

Section: Approachmentioning

confidence: 56%

Simple Dispersion Relations for Coulomb and Yukawa Fluids

IEEE Trans. Plasma Sci.

2018

“…In general, the inequality K ≥ K S holds [2]. Based on our previous experience with strongly coupled fluids with isotropic purely repulsive interactions, an approximate equality K K S can be expected [29][30][31]. In particular, in a recent study of fluids with IPL potentials (∝ r − ), this approximate relation has been verified in the entire region where the conventional expressions for the elastic moduli are applicable ( 25) [11].…”

Section: Miller's Resultsmentioning

confidence: 83%

Elastic properties of dense hard-sphere fluids

2019

Phys. Rev. E

A new analysis of elastic properties of dense hard sphere (HS) fluids is presented, based on the expressions derived by Miller [J. Chem. Phys. 50, 2733(1969]. Important consequences for HS fluids in terms of sound waves propagation, Poisson's ratio, Stokes-Einstein relation, and generalized Cauchy identity are explored. Conventional expressions for high-frequency elastic moduli for simple systems with continuous and differentiable interatomic interaction potentials are known to diverge when approaching the HS repulsive limit. The origin of this divergence is identified here. It is demonstrated that these conventional expressions are only applicable for sufficiently soft interactions and should not be applied to HS systems. The reported results can be of interest in the context of statistical physics, physics of fluids, soft condensed matter, and granular materials. arXiv:1910.00338v1 [cond-mat.mtrl-sci]