The random phase approximation integral equation is solved for obtaining the dynamically screened interaction between d electrons (Wd(ω)), p electrons (Wp(ω)) and p d electrons (Wpd(ω)). Some characteristic divergence of this last interaction correspond to the plasmon frequencies which one can relate with the effective masses of the p and d electrons close to EF by means of the relation ωp1 ωp2 = ( m2 m1) 1 2. ZAnother feature of this Wpd(ω) interaction is the attractive character for low frequencies. The lowest frequency for which εpd = 0 decreases when the localization of states close to EF arising from the χ2-y2 symmetry increases. © 1989.