RAMAN STUDIES OF INTACT AND SODIUM DOPED C-13-SUBSTITUTED POLY-P-PHENYLENE

The Raman and infrared spectra of C-13-substituted poly-p-phenylene (P PP) and the Raman spectra of Na-doped PPP excited at 488.0 and 1064 nm were observed and compared with the corresponding spectra for the ord inary (C-12) polymer. C-13 substitution is shown to be useful for char acterizing not only the bands of intact PPP but also those of polarons and bipolarons generated in Na-doped PPP. The number of Raman bands o bserved for bipolarons (and also for polarons) is greater than that fo r intact PPP. This observation is explained as the result of the loss of translational symmetry in the regions of these local excitations.