On the fluorescence of substituted oligothiophenes

An anomalous behavior of the fluorescence of substituted oligothiophenes (α-α′ linkages) as a function of the number of rings has been reported. In this work we have theoretically investigated this phenomenon. Theoretical characterizations of both ground and excited states of oligothiophenes were carried out through the use of sophisticated semi-empirical methods. Our results have shown that the experimentally observed charge transfer suppression can be explained in terms of the evolution and the nature of the electronic configurations.