Current state and problems in surface tension of solids, logical and experimental analysis of basic equations

Abstract

Of the four basic thermodynamic equations for the surface tension of solids: the generalized and classical Lippmann equations, and the Shuttleworth and Gokhshtein equations, only the Gokhshtein equation has been confirmed experimentally. The generalized Lippmann equation is generally considered to be more universal, since three other equations could be derived from it. This fact has been widely accepted, but recently it was reevaluated in two opposite ways. In the first approach, the experimental verification of the Gokhshtein equation should support the correctness of the generalized Lippmann and Shuttleworth equations. In the second approach, the incompatibility of the Shuttleworth equation with Hermann’s mathematical structure of thermodynamics raises doubts upon all its corollaries, including the generalized Lippmann and Gokhshtein equations. Both these logical approaches are shown to be erroneous, since the Gokhshtein equation cannot be correctly derived from any of the above-mentioned equations, and the opposite is also true: neither the generalized Lippmann nor Shuttleworth equations could be derived from the Gokhshtein equation. The high sensitivity of the contact electric resistance method to negative adsorbate charge allows detail investigation of the kinetics of the charge transfer during anion adsorption. For the fist time, this permits a tentative approach to quantify the potential dependence of the partial charge transfer during halide ions adsorption on IB metals.