Review of data for velocity of sound in pure liquid metals and metalloids

Abstract

A review of the experimentally determined values of the velocity of sound c in molten pure liquid metals and metalloids has been carried out. Based on the available data for each element, recommended velocity-temperature relationships have been suggested. A range of thermophysical properties has been derived from these values. Theoretical models for the velocity of sound and its temperature dependence have also been considered. Sound velocities have also been estimated via the inter-relationship of velocity to other thermophysical properties.

Anomalous and normal dependence of the sound velocity in the liquid Bi–Sb system

“…Whereas relatively extensive studies have been performed on many pure liquid elements [3], only a few studies have been made of the physical properties of the multitude of alloy systems [4][5][6][7][8][9]15,16], despite the relevance of the latter in applications and the possibility of encountering novel phenomenology due to the additional degree of freedom of the composition. Of the binary alloy systems, arguably the simplest is the isomorphous system where the solid phase remains in the same structure at all compositions along the solidus.…”

“…However, there also exist anomalous liquid metals such as Si, Ge, Sb and Te [3,13] that exhibit non-monotonic temperature dependence of the sound velocity , which first rises to a maximum and then proceeds to decrease. Semi-normal liquids have monotonic, but variable, temperature dependence of the sound velocity, such as Bi [3,12].…”

“…However, there also exist anomalous liquid metals such as Si, Ge, Sb and Te [3,13] that exhibit non-monotonic temperature dependence of the sound velocity , which first rises to a maximum and then proceeds to decrease. Semi-normal liquids have monotonic, but variable, temperature dependence of the sound velocity, such as Bi [3,12]. Focusing on the pnictides, a progression can be observed down the column from the significant sound velocity anomaly in As where the maximum in the temperature dependence has not yet been determined [14], through anomalous (positive) temperature dependence in Sb with a maximum at approximately 850 0 C [12], to semi-normal (variable) temperature dependence in Bi [12].…”

Dispersion relations of the acoustic modes in divalent liquid metals

“…It is known that Ω 1 does not coincide with the energy of the inelastic peak in S (Q, E)/S (Q) but approximate the peak energy of the current-current correlation function J(Q, E). The results of liquid Ca show that Ω 1 (black circles) at Q < 5 nm −1 disperses along with approximately 3900 m/s, which is 34 % faster than the ultrasonic sound speed of 2950 m/s [14]. This panel also depicts the excitation energy of the longitudinal acoustic mode predicted by the AIMD simulation.…”

“…Ω 1 at Q ∼ 5 nm −1 disperses along approximately 2600 m/s, which is 19 % faster than the ultrasonic sound speed of 2200 m/s [14]. The excitation energies of the longitudinal acoustic mode predicted by the AIMD simulation are plotted in the figure, using the same symbols in Fig.…”