Emission Properties of Tetracene—Pyrene and Pentacene—Pyrene Mixed Crystals

Studies of the emission spectra of tetracene- and pentacene-doped pyrene crystals reveal that tetracene is soluble in pyrene crystals only to the extent of one part in 104, whereas pentacene is soluble only to less than one part in 105. These results explain why tetracene and pentacene are ``anomalously'' poor quenchers of pyrene fluorescence and resolve an apparent conflict with current theories of energy transfer.