Author(s)

M. G. Velarde & V. M. Starov

Abstract

Using the DLVO (Derjaguin, Landau, Verwey, Overbeek) theory, which accounts for quantum mechanics and electrostatics at the macroscopic level, the thermodynamic expressions for (thermodynamic) equilibrium contact angles of drops on solid substrates and menisci in solid wall capillaries are, operationally and unambiguously, expressed in terms of the corresponding Derjaguin pressure. The latter’s S-shape is responsible for microdrops and other phenomena appearing on flat solid substrates. Keywords: DLVO, Derjaguin pressure, surface forces, wetting, drops, capillaries. 1 Introduction: mechanics versus thermodynamics In the study of the equilibrium of a sessile drop partially wetting a smooth, homogeneous, flat solid substrate, there have been numerous attempts to deduce the Young equation for the equilibrium contact angle, θ, [1-3]

Keywords

DLVO, Derjaguin pressure, surface forces, wetting, drops, capillaries