Surface Free Energy and Surface Stress as Elastic Components of the Surface Tension of Condensed Matter

摘要

The "surface free energy" and "surface stress" are basic notions in the current theory of the surface tension of solids; they were used online together or separately thousands times, but never "as elastic components of surface tension". Most of experts highlight that these different notions cannot be mixed or confused since the first one is of the "plastic" and second is of "elastic" nature. Below these opinions are shown to be incorrect. Sufficient evidences, both theoretical and experimental, demonstrate the elastic nature of both the "surface energy" and "surface stress". In this way, we considered the most convincible models of the metal surface based on the Coulomb interaction and purely elastic surface deformation. The reminiscent of the cantilever-beam-technique data and electrocapillary curves of mercury in combination with the specific adsorption data has logically led to the formulation of the "optimum surface electron density" notion (for the first time in the field of surface tension).