R. Anandhi et al., TRANSIENT ABSORPTION STUDIES ON 3,6-DIBROMO POLYVINYLCARBAZOLE AND ITS MODEL COMPOUNDS, Journal of photochemistry and photobiology. A, Chemistry, 106(1-3), 1997, pp. 135-139
3,6-Dibromo-N-ethylcarbazole (DBNEC) and its polymeric analogue poly-3
,6-dibromovinylcarbazole (PDBVCz) were studied by transient absorption
spectroscopy. The transient absorption spectrum of the 3,6-dibromo-N-
ethylcarbazole radical cation and decay rate constants of radical cati
ons of 3,6-dibromo-N-ethylcarbazole and its polymeric analogue are pre
sented. In the case of unsubstituted carbazole, the ratio of the yield
of radical cation of monomer to polymer is 2.0, whereas in the case o
f PDBVCz, under the same experimental conditions, the yield of the rad
ical cation is an order of magnitude less in comparison with the monom
er model compound DBNEC. This drastic difference in yield has been cor
related to the difference in the conformational structure of the polym
er as evidenced by nuclear magnetic resonance spectroscopy. (C) 1997 E
lsevier Science S.A.