ISSN:
1022-1352
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
The synthesis and characterization of a series of thienylenic α,ω-diformyl-α-oligothiophenes with 3, 6 and 8 residues is reported. The chemical structure was determined by 1H NMR, FT-IR, mass and GPC analyses, while the electronic properties in the neutral state were studied by UV-Vis spectroscopy both in solution and in the solid state. In the UV-Vis spectra of thin films, the vibronic structure is observed. The pronounced red-shift of the absorption maximum, with respect to spectra of unsubstituted α-oligothiophenes, is indicative of a contribution of carbonyl π-electrons to the overall delocalization via a mesomeric effect leading to a more planar structure. The solid state aggregation was investigated by XRD spectroscopy and optical microscopy. We observed for the longest terms a smectic arrangement typical of liquid crystalline compounds and a tendency to self-assembling onto hydrophilic substrates, forming angles ranging from 40-50° with respect to the normal to the surface.
Additional Material:
8 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/macp.1997.021980413
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