Optical and electronic properties of thin PDAs films with very narrow excitonic bandwidth

Soluble polycarbazolyldiacetylene systems (PCDAs) having long alkyl chains on the carbazolyl substituents have been recently prepared. In these system s, PCDAs chains in the solid state are assembled in hexagonal columnar stru ctures. Thin films of these PCDAs show a very high value for the third orde r susceptibility. In order to study the effect of the substituents in the e lectronic properties of PCDAs we have inserted -CO(CH2)(n)CH3 groups on the carbazolyl rings, thus decreasing the electron-donor effect of carbazole. Non-birefringent thin films of excellent optical quality are obtained whose optical and electronic properties are here reported.