The generation of superthermal electron populations due to resonant energy transfer from Alfvén wave packets can be studied sufficiently well within the Fokker-Planck diffusive formalism, where the particle energization is induced through Landau interaction. From the calculation of the magnetic-field-dependent diffusion operator of an Alfvén wave spectrum, it is demonstrated how resonant energization can be forced in nonuniform magnetic field configurations. On this basis, a mechanism for the acceleration of electrons from thermal to relativistic energies is presented where the specific magnetic field geometry acts as catalyst, providing a highly effective source for synergetic electron energization.