OPTICAL-PROPERTIES OF A LOW-ENERGY GAP CONDUCTING POLYMER - POLYDITHIENO[3,4-B-3',4'-D]THIOPHENE

We present here a new low energy gap conducting polymer belonging to the family of the fused thiophene molecules:p olydithieno[3,4b-3',4'd]thiophene(poly-DTT)I.t s optical properties have been extensively studied. The energy gap of this new polymer is of the order of 1.1 eV. The results derived from the electronic and vibrational spectra of the doped and undoped species are consistent with the bipolaron model. A strong electrochromic effect between a semitransparen(tc onducting)a nd an opaque( resistive)f orm hasb een observed.