Title of article :
Ultrafast excited-state proton transfer from dicyano-naphthol
Carmeli، نويسنده , , I. and Huppert، نويسنده , , D. and Tolbert، نويسنده , , L.M. and Haubrich، نويسنده , , J.E.، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 1996
The rate of proton transfer from electronically excited 5,8-dicyano-2-naphthol (DCN2) to the solvent is studied by time-resolved fluorescence. Unlike most naphthol derivatives, excited DCN2 is a strong acid (pK∗ 2≈ −4.5) and therefore is capable of transferring protons to alcohols and other moderate proton acceptor solvents. The rate constant of proton transfer, κd, at low temperatures (< 250 K) is slightly larger than the inverse dielectric relaxation time, 1/τD and has the same activation energy of the dielectric relaxation. On the other hand, at temperatures above 250 K the temperature dependence of the proton transfer rate decreases monotonically with increasing temperature, while the dielectric relaxation activation energy maintains the low temperature value.
Journal title :
Chemical Physics Letters