Chromophores in phenylenevinylene-based conjugated polymers: role of conformational kinks and chemical defects.
The influence of chemical defects and conformational kinks on the nature of the lowest electronic excitations in phenylenevinylene-based polymers is assessed at the semiempirical quantum-chemical level. The amount of excited-state localization and the amplitude of through-space (Coulomb-like) versus through-bond (charge-transfer-like) interactions have been quantified by comparing the results provided by excitonic and supermolecular models. While excitation delocalization among conjugated segments delineated by the defects occurs in the acceptor configuration, self-confinement on individual chromophores follows from geometric relaxation in the excited-state donor configuration. The extent of excited-state localization is found to be sensitive to both the nature of the defect and the length of the conjugated chains. Implications for resonant energy transfer along conjugated polymer chains are discussed.
Hennebicq
Emmanuelle
E
Laboratory for Chemistry of Novel Materials and Center for Research in Molecular Electronics and Photonics, University of Mons-Hainaut, Place du Parc 20, B-7000 Mons, Belgium. emmanuelle@averell.umh.ac.be
Deleener
Caroline
C
Brédas
Jean-Luc
JL
Scholes
Gregory D
GD
Beljonne
David
D
D002244:Carbon / Q000737:chemistry; D002627:Chemistry, Physical / Q000379:methods*; D004583:Electrons; D004735:Energy Transfer; D008956:Models, Chemical; D015233:Models, Statistical; D008968:Molecular Conformation; D011108:Polymers / Q000737:chemistry*; D011145:Polyvinyls / Q000737:chemistry*; D011336:Probability; D011789:Quantum Theory; D012680:Sensitivity and Specificity
D011108:Polymers; D011145:Polyvinyls; C470024:poly(4-phenylenevinylene); D002244:Carbon