  We investigate the influence of a stochastically fluctuating step-barrier
potential on bimolecular reaction rates by exact analytical theory and
stochastic simulations. We demonstrate that the system exhibits a new resonant
reaction behavior with rate enhancement if an appropriately defined fluctuation
decay length is of the order of the system size. Importantly, we find that in
the proximity of resonance the standard reciprocal additivity law for diffusion
and surface reaction rates is violated due to the dynamical coupling of
multiple kinetic processes. Together, these findings may have important
repercussions on the correct interpretation of various kinetic reaction
problems in complex systems, as, e.g., in biomolecular association or
catalysis.
