WHAT DOES CEF�?CRYSTAL MEAN?

The luminescence of nanocrystalline ZnS : Mn2+ in fact shows a short decay time ingredient (∼100 ns), but in addition a lengthy (ms) decay time is noticed. The brief decay time is ascribed into a defect-connected emission of ZnS, and is not with the decay of the changeover in the Mn2+ impurity. The changeover of the Mn2+ incorporates a `usual�?