Generality of Adjustable Physical Parameter in Classical Density Functional Approximation

摘要

This paper checks the generality problem of an adjustable physical parameter in classical density functional (DF) approximation, here, the "generality" means independence of numerical value of the adjustable physical parameter on the external field generating the density inhomogeneity. It is found that the more accurate the relevant DF approximations are, the more effective the generality of the adjustable physical parameter. The present analysis proves the validity of using a single planar hard wall sum rule for ascertaining unknown physical parameter.