15 research outputs found
Limits of structure stability of simple liquids revealed by study of relative fluctuations
We analyse the inverse reduced fluctuations (inverse ratio of relative volume
fluctuation to its value in the hypothetical case where the substance acts an
ideal gas for the same temperature-volume parameters) for simple liquids from
experimental acoustic and thermophysical data along a coexistence line for both
liquid and vapour phases. It has been determined that this quantity has a
universal exponential character within the region close to the melting point.
This behaviour satisfies the predictions of the mean-field (grand canonical
ensemble) lattice fluid model and relates to the constant average structure of
a fluid, i.e. redistribution of the free volume complementary to a number of
vapour particles. The interconnection between experiment-based fluctuational
parameters and self-diffusion characteristics is discussed. These results may
suggest experimental methods for determination of self-diffusion and structural
properties of real substances.Comment: 5 pages, 4 figure