Pseudo-Grüneisen Parameter for Liquids

Abstract

The dimensionless parameter $\frac{{V_h}^2\alpha }{C_p}$ is investigated for liquids, where $V_h$ is the velocity of sound, and $\frac{\alpha }{C_p}$ the ratio of the coefficient of thermal expansion to the specific heat at constant pressure. For both Hg and ${\mathrm{H}}_2$O, this quantity increases with increasing compression, contrary to the behavior for solids. For ${\mathrm{H}}_2$O, this parameter becomes substantially independent of temperature. For a model in which compaction is assumed to take place by an increase of long-range positional order and growth of clusters, the pseudo-Grüneisen parameter is predicted to be temperature independent.