LONG-LIVED PHOTOEXCITED STATES IN POLYDIACETYLENES WITH DIFFERENT MOLECULAR AND SUPRAMOLECULAR ORGANIZATION

With the aim of determining the importance of the molecular and supram olecular organization on the excited states of polydiacetylenes, we ha ve studied the photoinduced absorption spectra of the redform of 1,6-b is(3,6-didodecyl-N-carbazolyl)-2,4-hexadiyne] (polyDCHD-S) and the res ults compared with those of the blue form of the same polymer. An inte rpretation of the data is given in terms of both the conjugation lengt h and the interbackbone separation also in relation to the photoinducc d absorption spectra of both blue and red forms of poly[1,6-bis(N-carb azolyl)-2,4-hexadiyne] (polyDCHD), which does not carry the alkyl subs tituents on the carbazolyl side groups. Information on the above prope rties is derived from the analysis of the absorption and Raman spectra of this class of polydiacetylenes. [S0163-1829(97)03039-7].