Differential cross sections for the elastic scattering of 17O on 12C and the inelastic excitation of 17O to its first excited 1/2+ state are calculated within the molecular particle-core model. This model decomposes the 17O+12C system into a 12C and 16O core with an extra neutron described by molecular eigenstates of the two-centre shell-model Hamiltonian. Depending on the coupling strength the enhancement of the radial coupling due to an avoided level crossing can generate structures in the angle-integrated inelastic excitation function. These energy-dependent structures are related to resonance states of the relative motion in the elastic channels and are caused by the nuclear Landau-Zener effect.