  The nuclear isovector-dipole strength structure is analyzed in terms of the
main and satellite (pygmy) peaks within the Fermi-liquid droplet model. Such a
structure is sensitive to the value of the surface symmetry-energy constant
obtained analytically for different Skyrme forces in the leptodermous effective
surface approximation. Energies, sum rules and transition densities of the main
and satellite peaks for specific Skyrme forces are qualitatively in agreement
with the experimental data and other theoretical calculations.
