“…This is, however, different for systems with reversible reactions, as these systems generically display power-law relaxation, independent of the values of the reaction and diffusion rates [16,17,18,19,20,21,22,23,24,25,26]. Studies of excited-state proton transfer reactions provided experimental verifications of this theoretically predicted behavior [27,28,29]. This of course makes the diffusion-limited systems with reversible reactions very attractive for a study of aging processes.…”