Curved and diffuse interface effects on the nuclear surface tension

We redefine the surface tension coefficient for a nuclear Fermi-liquid drop with a finite diffuse layer. Following the Gibbs-Tolman concept, we introduce the equimolar radius R-e of the droplet surface at which the surface tension is applied and the radius of tension surface R-s which provides the minimum of the surface tension coefficient sigma. This procedure allows us to derive both the surface tension and the corresponding curvature correction (Tolman length) correctly for the curved and diffuse interface. We point out that the curvature correction depends significantly on the finite diffuse interface. We show that Tolman's length xi is negative for a nuclear Fermi-liquid drop. The value of the Tolman length is only slightly sensitive to the Skyrme force parametrization and equals xi = -0.36 fm.