Intensive Chiroptical Properties of Chiral Polyfluorenes Associated with Fibril Formation
| Autor: | Peter C. M. Christianen, Jeroen C. Gielen, Martijn Kemerink, Stefan C. J. Meskers, René A. J. Janssen, Girish Lakhwani |
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| Přispěvatelé: | Macromolecular and Organic Chemistry, Molecular Materials and Nanosystems |
| Rok vydání: | 2009 |
| Předmět: |
Length scale
Circular dichroism Chloroform Materials science Stereochemistry Correlated Electron Systems / High Field Magnet Laboratory (HFML) Fibril Surfaces Coatings and Films chemistry.chemical_compound Crystallography chemistry Materials Chemistry Degree of polarization Molecule Physical and Theoretical Chemistry Thin film Spectroscopy |
| Zdroj: | Journal of Physical Chemistry B, 113(43), 14047-14051. American Chemical Society Journal of Physical Chemistry B: Condensed Matter, Materials, Surfaces, Interfaces and Biophysical, 113, pp. 14047-15051 Journal of Physical Chemistry B: Condensed Matter, Materials, Surfaces, Interfaces and Biophysical, 113, 14047-15051 |
| ISSN: | 1520-5207 1520-6106 |
| DOI: | 10.1021/jp903083x |
| Popis: | Thin films of chiral poly{9,9-bis[(3S)-3,7-dimethyloctyl]-2,7-fluorene} (1) were studied using circular dichroism (CD) spectroscopy. Films spin coated from chloroform solution, show CD with a degree of polarization g(abs) (= +4 x 10(-4) at 400 nm) that is independent of film thickness (50-290 nm). This implies that g(abs) is an intensive property of the material and related to the chiral organization of the molecules on a length scale less than 50 nm. Atomic force microscopy (AFM) on the films reveals fibrils. Addition of nonsolvent methanol to a solution of 1 in chloroform leads to fibril formation in solution and results in CD similar in band shape to that of the pristine spin coated films from chloroform solution and a g(abs) comparable in magnitude. Thus the chiral molecular arrangement leading to circular dichroism is part of the internal structure of these fibrils. |
| Databáze: | OpenAIRE |
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