Isovector properties of Skyrme-type effective interactions

Simple relations between the parameters of Skyrme-type interactions and the mean energies of isovector monopole, isovector dipole and Gamow-Teller resonances are derived in order to examine the isovector spin-independent and spin-dependent parts of the interaction. It is checked that these relations reproduce well the energies of RPA calculations using 208Pb as a test nucleus. We propose to include them as new, additional constraints when determining effective interactions to be used in neutron-rich or proton-rich nuclei.