Fluorescence and excited‐state structure of conjugated polymers

The electronic structure of conjugated polymers can be understood to a certain extent by applying the Pariser‐Parr‐Pople model for interacting π‐electrons in conjugated molecules. In this review, particular emphasis is laid on spectroscopic and theoretical studies of conjugated polymers in which different types are compared. The electroluminescence behavior is of special interest. The nature of the lowest singlet excitation is found to determine whether, in general, the flourescence is stron or weak.