Interfacial Premelting and the Thermomolecular Force: Thermodynamic Buoyancy

A. W. Rempel; J. S. Wettlaufer; M. G. Worster

doi:10.1103/PhysRevLett.87.088501

Interfacial Premelting and the Thermomolecular Force: Thermodynamic Buoyancy

A. W. Rempel, J. S. Wettlaufer, and M. G. Worster

Phys. Rev. Lett. 87, 088501 – Published 7 August 2001

Abstract

The presence of a substrate can alter the equilibrium state of another material near their common boundary. Examples include wetting and interfacial premelting. In the latter case, temperature gradients induce spatial variations in the thickness of the premelted film that reflect changes in the strength of the repulsion between the substrate and the solid. We show that the net thermomolecular force on a macroscopic substrate is equivalent to a thermodynamic buoyancy force—proportional to the mass of solid that can occupy the volume enclosed by the substrate and the temperature gradient.

Received 20 March 2001

DOI:https://doi.org/10.1103/PhysRevLett.87.088501

Authors & Affiliations

A. W. Rempel¹ and J. S. Wettlaufer^1,2

¹Applied Physics Laboratory, University of Washington, Seattle, Washington 98105-55640
²Department of Physics, University of Washington, Seattle, Washington 98195-51560

M. G. Worster

Institute of Theoretical Geophysics, Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Silver Street, Cambridge CB3 9EW, United Kingdom