A patching model for surface tension and the Tolman length

In the framework of density functional theory (DFT), a patching model for the density profile of the liquid-vapor interface is developed. The patching is based on analytical expressions of the asymptote of the density profiles. Derived from the model the surface tension of planar liquid-vapor interface as well as the Tolman length can be computed from analytic expressions. Two prototype systems are considered; the Yukawa and the Lennard-Jones. As a result, the temperature dependence of the surface tension as well as the Tolman length are obtained. The results are compared with numerical DFT calculations. (C) 1999 American Institute of Physics. [S0021-9606(99)70232-1].