DESIGN OF SMALL-GAP CONJUGATED POLYMERS

Design of small energy gap conjugated polymers rests on the understand ing of the geometric and electronic structure of prototypical systems followed by calculations and predictions of closely related derivative s and modifications. Calculations employed use periodic boundary condi tion and are based on geometry optimization, since the energy levels a round the Fermi level are strongly coupled to the geometry. We conside r prototypes, based on thiophene derivatives and silicon containing po lymers.