6533b81ffe1ef96bd1277e17

RESEARCH PRODUCT

Effective conjugation in conjugated polymers with strongly twisted backbones: A case study on fluorinated MEHPPV

Manef AbderrabbaBegoña Milián-medinaBegoña Milián-medinaAranzazu AguirreJunqing ShiAntonio CardoneJohannes GierschnerRim MiladRim MiladGianluca M. Farinola

subject

chemistry.chemical_classificationfluorinated MEHPPVMaterials scienceQuenching (fluorescence)twisted backbones02 engineering and technologyGeneral ChemistryPolymerConjugated system010402 general chemistry021001 nanoscience & nanotechnologyPhotochemistry01 natural sciencesFluorescence0104 chemical sciencesChain lengthPlanarchemistryExcited stateEffective conjugationMaterials ChemistryEmission spectrum0210 nano-technology

description

Conjugated polymers with strongly twisted backbones, such as MEHPPV with fluorinated vinylene units (F-MEHPPV), demand a redefinition of the all-important ‘effective conjugation length’ ECL, which we extract here by a facile graphical method. In MEHPPV (being essentially planar), the ECL coincides with the ‘maximum conducive chain length’ MCC and extends over about n ≈ 9 repetition units (RU). In F-MEHPPV, the MCC is similarly long with n ≈ 8, but the ECL localizes on just one RU. The strong twist in F-MEHPPV persists in the excited state, broadening the emission spectrum and quenching the fluorescence with reduced radiative and enhanced non-radiative rates.

yearjournalcountryeditionlanguage
2016-01-01
10.1039/c6tc01720ghttp://hdl.handle.net/20.500.12614/2433