EFFECT OF INTERCHAIN SEPARATION ON THE PHOTOINDUCED ABSORPTION-SPECTRA OF POLYCARBAZOLYLDIACETYLENES

The photoinduced absorption spectra of a novel polycarbazolyldiacetyle ne with long aliphatic chains on the carbazolyl side groups are measur ed and compared with those of the unsubstituted polyDCHD. The two poly mers in the blue form exhibit very similar electronic absorption spect ra and Raman frequencies. This fact indicates that the conjugation len gth of the polydiacetylene backbone is not too affected by the long su bstituents. In contrast, the near steady-state photoinduced absorption spectra show that different photogeneration mechanisms are involved i n the two polymers. This result can be ascribed to the role played by the interchain distance in the dynamics of the relaxation processes in polydiacetylenes.