Influences of binding transitions on the homogeneous nucleation of mercury

Abstract

Nucleation rates from supersaturated vapor are calculated for mercury. Previous measurements of nucleation rates using an upward thermal diffusion chamber demonstrated that critical supersaturations for Hg vapor are roughly three orders of magnitude lower than the predictions of the classical Becker-Doring-Zeldovich theory. [J. Martens, H. Uchtmann, and F. Hensel, J. Phys. Chem. 91, 2489 (1987)] This discrepancy was attributed to a metal-nonmetal transition in Hg clusters that occurs near the critical cluster size. [H. Uchtmann, K. Rademann, and F. Hensel, Annalen der Physik. 48, 207 (1991)] That view is supported by the similarity of cohesive energies and optical spectra for Hg clusters and rare gas clusters. [H. Haberland et al., Z. Phys. D 26, 8 (1993)] Using this analogy and the framework of the classical theory, we calculate nucleation rates that agree with the experiments within experimental uncertainties without any adjustable parameters.

Group Members

William A. Goddard III

Charles and Mary Ferkel Professor