https://doi.org/10.1351/goldbook.D01579
Three types of delayed
fluorescence
are known: - E-type delayed fluorescence: The process in which the first excitedsinglet statebecomes populated by a thermally activatedradiationless transitionfrom the first excitedtriplet state. Since in this case the populations of the singlet and triplet states are in thermal equilibrium, the lifetimes of delayedfluorescenceand the concomitantphosphorescenceare equal.
- P-type delayed fluorescence: The process in which the first excitedsinglet stateis populated by interaction of two molecules in thetriplet state(triplet-tripletannihilation) thus producing one molecule in the excitedsinglet state. In thisbiphotonic processthelifetimeof delayedfluorescenceis half the value of the concomitantphosphorescence.
- Recombination fluorescence: The first excited singlet statebecomes populated by recombination ofradical ionswith electrons or by recombination of radical ions of opposite charge.
See also:
delayed luminescence