BENDING RIGIDITIES AND SPONTANEOUS CURVATURE FOR A SPHERICAL INTERFACE

We report on a study of the free energy of a spherical interface descr ibed by a van der Waals density functional with a squared-laplacian te rm. We examine the bulk, the surface tension and the bending rigidity terms, and find the position for the dividing surface that satisfies t he Laplace equation generalized to nonvanishing bending energy. in doi ng this we have made explicit the connection between two previously de rived but dissimilar sets of expressions for the interfacial coefficie nts that stem from the same free energy model (one by Romero-Rochin et al. (Phys. Rev. A 44 (1991) 8417; Phys. Rev. E 46 (1993) 1600) and th e other by Gompper and Zschocke (Europhys. Lett. 18 (1991) 731) and by Blokhuis and Bedeaux (Mel. Phys. 80 (1993) 705).