Lowest luminescent conjugated polymers

The lowest excited states in luminescent conjugated polymers are very similar to the dyes used in dye lasers (Chapter 3, section 3.5.3). Therefore the conjugated polymers can be used to achieve population inversion by optical pumping as with the laser dyes. 

We now turn to a discussion of the issue related to the nature of the emitting species in the lowest excited state of luminescent conjugated polymers, with the help of theoretical calculations including both electron-phonon and electron-electron interactions. Specifically, we address the following propositions that have been reported in the literature ... 

Following photoexcitation from the ground state (lAg in the notation of molecular spectroscopy) to the lowest energy state with proper symmetry (1B ), recombination to the ground state can be either radiative (with the emission of light, i.e. luminescence) or non-radiative. Some families of conjugated polymers... 

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