TEMPERATURE-DEPENDENCE OF FLUORESCENCE LIFETIME OF 2-NAPHTHOL IN ICE (I-H) CRYSTAL - A STUDY OF THE PROTON MOTION IN ICE

The lifetime of the fluorescence from 2-naphthol (C10H8OH) doped in ic e I-h was measured from 27 to 300 K. The slow component tau(s) (5.3 ns at 27 K) shows a significant decrease in the temperature range 130-20 0 K, while the faster component (tau f approximate to 0.7 ns) shows a slight decrease above 200 K. The relative intensity I-f/I-s increases above 130 K. The results were interpreted in terms of a model involvin g the transfer between the two states, S-1 and S-1 which correspond to the excited states of 2-naphthol with and without considering the tra pping of proton with L defects in ice, respectively.