Electronic structure of conjugated regular copolymers: Fine tuning of band gap value

The recent discovery that conjugated polymers can effectively function as active materials in light-emitting diodes has increased the interest in the fine tuning of their optical gaps. Copolymers are very promising in this context as they can boost the efficiency of the recombination processes. We present here the results of quantum chemical calculations aimed at determining the evolution of the electronic properties as a function of the unit cell content in regular block copolymers of poly (p-phenylene) and polyacetylene. In this case, the bandgap can be tuned over the whole visible range, depending on the extent of the block copolymer sequences.