EMISSION CHARACTERISTICS OF SILVER ATOMS IN GAMMA-IRRADIATED ORGANIC-SOLID SOLUTIONS AT 77 K

Ag-0 atoms were produced via the electron capture of Ag+ ions in gamma -irradiated solid solutions of ethanol and MTHF at 77 K. The 2-dimensi onal time-resolved fluorescence spectra together with the steady-state fluorescence spectra and excitation spectra were measured by photoexc itation of Ag-0 produced in the gamma-irradiated solid solutions. The steady state measurements have revealed the existence of two main emis sion bands at nearly 500 and 580 nm. The intensity of the 500 nm band increased and that of the 580 nm band concomitantly decreased with inc reasing concentration of Ag+ in both solutions. The time-resolved obse rvation has shown that the 500 nm band consists of three components of different lifetimes (tau). The main component with tau similar to 1 m u s is attributed to the exciplex (Ag-0. Ag+), the one with tau simil ar to 2 mu s, to the similar exciplex which is weakly coupled to solve nt molecules, and the third one with tau similar to 3 ns, to Ag-0 tra pped in a large cavity where Ag-0 scarcely interacts with solvent mole cules. The 580 nm band grows at about 0.5 - 1 mu s and decays with a l ong Lifetime, i.e., about 50 mu s in ethanol or 40 mu s in MTHF. The b and is attributed to the exciplex (Ag-0. L-n), where L-n denotes n so lvent molecules.