Luminescent homoatomic exciplexes in dicyanoargentate(I) ions doped in alkali halide crystals. 2. "Exciplex tuning" by varying the dopant concentration

The dependence of the dicyanoargentate(I) luminescence on the dopant concen tration in [Ag(CN)(2)(-)]/KCl single crystals is reported. Three crystals w ith different Ag content have been studied. The photoluminescence spectrum of the doped crystal that has the lowest silver content (0.17%) is dominate d by a high-energy band at similar to 295 nm, while the spectrum with the h ighest silver content (4.3%) is dominated by a low-energy luminescence band at similar to 400 nm. The crystal with an intermediate Ag content (2.7%) s hows strong emissions from both the high-energy and low-energy bands. Time- resolved luminescence measurements indicate that the excitation energy is t ransferred between different [Ag(CN)(2)(-)], oligomers and, thus, leads to the tunable emission observed in the [Ag(CN)(2)(-)]/KCl system. The mechani sms of the radiative and nonradiative processes have been described by a ki netic model that describes the experimental lifetime and time-resolved data .