Polythiophenes electronic structure

Dannetun P, Boman M, Stafstrom S, Salaneck WR, Lazzaroni R, Fredriksson C, Bredas JL, Zamboni R, Taliani C (1993) The chemical and electronic structure of the interface between aluminum and polythiophene semiconductors. J Chem Phys 99(l) 664-672 Ahn H, Whitten JE (2003) Vapor-deposition of aluminum on thiophene-terminated self-assembled monolayers on gold. J Phys Chem B 107(27) 6565-6572 Fisher GL, Flooper A, Opila RL, Jung DR, Allara DL, Winograd N (1999) The interaction between vapor-deposited A1 atoms and methylester-terminated self-assembled monolayers studied by time-of-flight secondary ion mass spectrometry, X-ray photoelectron spectroscopy and infrared reflectance spectroscopy. J Electron Spectrosc Relat Phenom 98-99 139-148... 

Optical Properties of Polythiophenes Electronic Band Structure and UV-Visible Spectra... 

In the following, in particular the electronic structure of molecules in thin films as a function of their chain length will be presented, whereas spectra in solvents and of polythiophene are only given for comparison and the influence of substituents is only stressed briefly. 

As the electronic structure of the frontier orbitals in the sp -hybridized polythiophene chain is due to the overlap of the p -orbitals of carbon atoms in the chain, leading to the bonding n and anti-bonding n bands, any disturbance to this overlap will lead to changes of the electronic structure. The dimerization of the carbon chain—the modulation of the carbon-carbon distance—is already there in polythiophene, and this dimerization contributes to the band-gap [26]. Small... 

The coupling of the electronic structure of the conjugated polythiophene to the conformation can account for chromic phenomena as well as for aspects of electronic transport of the materials in their undoped or doped states. The order-disorder transition of the polymer chains, between a planar and a non-planar state, is governed by molecular mechanisms related to the nature and regularity of side-chain substituents. 

Li, L. Collard, D.M. Tuning the electronic structure of conjugated polymers with fluoroalkyl substitution alternating alkyl/perfluoroalkyl-substituted polythiophene. Macromolecules 2005, 38, 372-378. 

Raman spectra of doped polythiophene exhibit also modifications provided excitation wavelengths are taken in the red range. The main Ag mode is shifted to 1411 cm. An analysis of these spectra in the frame of our method, i.e. by modifying the main force constants associated to the bonds of the polymer backbone, leads also to a good fit of the modified Raman spectra. In contrary to doped PPP or doped PPV, it is not obvious whether the quinoid structure appears clearly. Instead, we do need to modify the C-S force constant, putting in evidence that the S atom plays a certain role in the electronic structure modification. Further details on the calculations will also be published elsewhere. 

Li Y, Nese A, Hu X, Lebedeva NV, LaJoie TW, Burdyhska J, Stefan MC, You W, Yang W, Matyjaszewski K, Sheiko SS (2014) Shifting electronic structure by inherent tension in molecular bottlebrushes with polythiophene backbones. ACS Marco Lett 3 738... 

Lan, Y.K., Yang, C.H., Yang, H.C., 2010. Theoretical investigations of electronic structure and charge transport properties in polythiophene-based organic held-effect transistors. Polym. Int. 59,16-21. 

Salzner, U., Lagowski, J., Pickup, P, Poirier, R., 1998. Comparison of geometries and electronic structures of polyacetylene, polyborole, polycyclopentadiene, polypyrrole, polyfuran, polysilole, polyphosphole, polythiophene, polyselenophene and polyteUurophene. Synth. Met. 96,177-189. 

Hong, S.Y., and D.S. Marynick. 1992. Understanding the conformational stability and electronic structures of modified polymers based on polythiophene. Macromolecules 25 4652. 

The other group of materials, which covers the electronic conductors, includes conjugated polymers whose electronic structure may be significantly modified by electrochemical processes, sometimes designated as doping processes, which involve the oxidation (removal of n electrons) or the reduction (addition of n electrons) of the polymer chain. Typical examples are the heterocyclic polymers, such as polypyrrole, polythiophene and their derivatives, and the polyanilines. 

J. E. Bredas, B. Themans, J. G. Fripiat, J. M. Andre, R. R. Chance, Highly conducting polyparaphenylene, polypyrrole and polythiophene chains - an ah initio study of the geometry and electronic structure modifications upon doping, Physical Review B 1984, 29, 6761. 

K. Bakhshi, J. Ladik and M. Seel, Comparative study of the electronic structure and conduction properties of polyp5nrole, polythiophene and polyfuran and their copolymers, Phys. Rev. B, 35, 704-712 (1987). 

K. Tanaka, S. Wang and T. Yamabe, Electronic structures of substituted derivatives of polythiophene. Design of narrvw-band-gap polymers, Synth. Mel, 30, 57-65 (1989). 

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