The effect of conjugation length distribution on the properties of modified PPV

The aim of this work was to demonstrate the optical properties of a copolymer involving alternating poly(para-phenylene–vinylene) and ether groups derived from the conjugation length distribution. For this, the time-dependent density functional theory (TD-DFT) was used. Thus, different conjugation lengths were considered, where the correlation of the corresponding theoretical spectra, including Raman, optical absorption and photoluminescence, allows us to conclude that the conjugation length distribution is caused by a random distribution of the ether blocks. The weight of each conjugation length representing its contribution is shown by the use of the Raman spectra. Furthermore, the theoretical spectra arising from the response of different conjugation lengths are obtained and compared with the experimental ones.