KINETICS OF SENSITIZED FLUORESCENCE OF NAPHTHALENE SINGLE-CRYSTALS DOPED WITH 2-METHYLNAPHTHALENE AND ANTHRACENE

The kinetics of the sensitized flourescence in naphthalene crystals doped with 2-methylnaphthalene (2-MN) and anthracene (A) was studied as a function of the temperature. These experiments yield singlet exciton diffusion constants of (2 ± 1) × 10-4 cm2 s-1 at 4.2 K and roughly 10-5 cm2 s-1 at 300 K. The exciton trapping radii can be estimated to be of the order of 60 Å for A and 10 Å for 2-MN. At temperatures below 40 K a partially coherent exciton motion can be inferred, above 40 K the exciton motion appears to be purely incoherent. © 1978.