Differential cross sections for proton elastic and inelastic scattering have been measured at ${E}_{p}=22.3$ MeV for 14 nuclei with $92\ensuremath{\le}A\ensuremath{\le}116$. The energy dependence has been studied between 10 and 35 MeV, considering also reaction cross sections at lower incident energies. The long standing sub-Coulomb optical model anomalies are thereby eliminated. Nuclear structure effects found in the analysis of elastic scattering are identified with strong couplings between ground and one-phonon states. These couplings are satisfactorily described by traditional collective models, using deformation parameters in agreement with those deduced from electromagnetic data. The transitions to weakly excited states require a more accurate spectroscopic description. Spectroscopic amplitudes taken from the interacting boson model are used. The radial dependence of transition densities is derived from optical model potentials.NUCLEAR REACTIONS Proton scattering on $^{92,94,96,98,100}\mathrm{Mo}$, $^{102}\mathrm{Ru}$, $^{104,106,108,110}\mathrm{Pd}$, and $^{106,110,112,116}\mathrm{Cd}$; ${E}_{p}=22.3$ MeV; on $^{104}\mathrm{Pd}$ at ${E}_{p}=10.25, 12.1, 15.0, 17.3, 22.3, 30.2, \mathrm{and} 35.4$ MeV. Measured $\ensuremath{\sigma}(\ensuremath{\theta})$; enriched targets. Optical model and coupled channels analyses. Collective vibrational model, coupling parameters. Interacting bosons approximation, form factors.