Optical, Redox, and NLO Properties of Tricyanovinyl Oligothiophenes: Comparisons between Symmetric and Asymmetric Substitution Patterns
作者:Juan Casado、M. Carmen Ruiz Delgado、M. Carmen Rey Merchán、Víctor Hernández、Juan T. López Navarrete、Ted M. Pappenfus、Nathaniel Williams、William J. Stegner、Jared C. Johnson、Brett A. Edlund、Daron E. Janzen、Kent R. Mann、Jesús Orduna、Belén Villacampa
DOI:10.1002/chem.200501389
日期:2006.7.17
role of conformational flexibility in the disubstituted compounds and reveal an unexpected nonlinear optical activity for symmetric molecules. Regarding the electronic structure, the interpretation of the vibrational data reflects the balanced interplay betweenaromatic and quinoid forms, finely tuned by the chain length and substitution pattern. The electronic and structural properties are consistent
Synthesis and Characterization of Tricyanovinyl-Capped Oligothiophenes as Low-Band-Gap Organic Materials
作者:Ted M. Pappenfus、Michael W. Burand、Daron E. Janzen、Kent R. Mann
DOI:10.1021/ol034317q
日期:2003.5.1
[GRAPHICS]Tricyanovinyl-capped oligothlophenes of up to six rings have been synthesized and characterized. The substituted oligomers display dramatic reductions in both their optical and electrochemical band gaps in comparison to unsubstituted oligomers. The solvatochromic behavior of the terthiophene-substituted molecule was investigated in a variety of solvents. Stable oxidations and reductions were exhibited by the sexithiophene-substituted molecule on the CV time scale.
Three oligothiophene dithiols with different numbers of thiophene rings (3, 6 or 9) have been synthesized and characterized. The X-ray singlecrystalstructures of terthiophene 2 and sexithiophene 5 are reported herein to show the exact molecular lengths, and to explain the difference between their UV-visible spectra arising from the different packing modes. These dithiols with different chain lengths