The decay lifetime of NaCl:Ag+ fluorescence: a new interpretation

The fluorescence of Ag+ in NaCl was investigated in the range of 21–300 K, in particular by performing accurate lifetime measurements. Lifetime values in the range of 21–100 K are consistent with the Pedrini model for Cu+ and Ag+ de-excitation. In contrast, lifetime values above 100 K are not consistent with the relationship involved in such a model simply because above 100 K the relative fluorescence quantum yield is not unity; this explains the puzzling results obtained in the past by Pedrini in NaCl:Ag+. Lifetime data were found irrespective of Ag+ concentration in the samples.