Singlet exciton diffusion and exciton quenching in phenanthrene single crystals

Singlet exciton surface processes have been investigated in phenanthrene single crystals with neat crystal surfaces and photo-oxidized surfaces. It is shown that two different surface conditions can be achieved experimentally; namely, an exciton quenching and a non-quenching surface. A quantitative analysis of the observed exciton quenching effect yields a singlet exciton diffusion length of 1380 Å. © 1976.