  We study the dipole response associated with the Pygmy Dipole Resonance (PDR)
and the Isovector Giant Dipole Resonance (IVGDR), in connection with specific
properties of the nuclear effective interaction (symmetry energy and momentum
dependence), in the neutron-rich systems $^{68}$Ni, $^{132}$Sn and $^{208}$Pb.
We perform our investigation within a microscopic transport model based on the
Landau-Vlasov kinetic equation. We observe that the peak energies of PDR and
IVGDR are shifted to higher values when employing momentum dependent
interactions, with respect to the results obtained neglecting momentum
dependence. The calculated energies are close to the experimental values and
similar to the results obtained in Hartree-Fock (HF) with Random Phase
Approximation (RPA) calculations.
