Europhys. Lett.
Volume 65, Number 2, January 2004
Page(s) 221 - 227
Section Condensed matter: structure, mechanical and thermal properties
Published online 01 January 2004
Europhys. Lett., 65 (2) , pp. 221-227 (2004)
DOI: 10.1209/epl/i2003-10068-4

Scaling frequency in the critical sound attenuation of binary liquids

R. Behrends and U. Kaatze

Drittes Physikalisches Institut, Georg-August-Universität Bürgerstrasse 42-44, 37073 Göttingen, Germany

(Received 15 July 2003; accepted in final form 6 November 2003)

For the ethanol-dodecane and methanol-cyclohexane mixtures of critical composition ultrasonic attenuation, shear viscosity, and dynamic light scattering data are evaluated to yield the scaled half-attenuation frequency $\Omega_{1/2}$ of the Bhattacharjee-Ferrell dynamic scaling model as well as the Folk-Moser and the Onuki scaling functions. Within the limits of experimental error, the experimental half-attenuation frequency values for the former model ( $\Omega_{1/2}^{\ab{BF}}=2.0\pm 0.5$) agree with the theoretical prediction. The $\Omega_{1/2}$ values derived for the Folk-Moser and the Onuki scaling functions exhibit systematic deviations from the theoretical values $\Omega_{1/2}^{\ab{FM}}=3.1$ and $\Omega_{1/2}^{\ab{On}}=6.2$. The results show that, at least for systems without crossover to elementary chemical reactions, the frequency scale in the dynamic scaling model, which had been obtained by including a special hydrodynamic effect, is in accord with experimental evidence.

68.35.Rh - Phase transitions and critical phenomena.
62.60.+v - Acoustical properties of liquids.

© EDP Sciences 2004