Dual asymptotic behavior in geminate diffusion-influenced reaction

The kinetics of excited-state proton transfer to solvent from the strong photoacid 5-cyano-2-naphthol exhibits two different power-law asymptotic tails for acid and base, arising from competition between reversible and irreversible geminate reprotonation. We show that the data are in quantitative agreement with a recently developed theory for this diffusion-influenced reaction.