Donor-acceptor conjugated

Figure 15-26. Schematic illustration of a device fabricated lroin a single layer of an interpenetrating donor-acceptor (conjugated polymer/CWi) network.

Molecules with donor and acceptor in trans- and a s-configurations give much higher nonlinearities, due to favorable linear donor-acceptor conjugation, than those with substituents at the geminal position, where only the weaker cross-conjugation is effective (see 89 vs 86 and 92, Fig. 8). 

Wu MW, Conwell EM (1998) Theory of photoinduced charge transfer in weakly coupled donor-acceptor conjugated polymers application to an meh-ppv cn-ppv pair. Chem Phys 227 11... 

Conclusively, in the low-concentration regime (10-6 M-1), where the electron donor-acceptor conjugates are present in their monomeric form, intramolecular electron-transfer processes, which are mainly governed by through-space interactions have been demonstrated by steady-state and time-resolved spectroscopic techniques. 

We have demonstrated that the donor-acceptor conjugates 18a,b exhibit efficient charge-transfer processes upon photoexcitation over distances of more than 24 A. The charge-transport mechanisms are comparable to those established for the corresponding exTTF-oPPV -C6o and exTI -oPP, systems. In view of the molecular-wire behavior of the oFLs, we have shown that in fluorene-based oligomers the ability to conduct charges lies between that of oPPVs and that of... 

In the context of oligo-fluorene (oFL) molecular wires, we will conclude with an outlook that focuses on donor-acceptor conjugates bearing Ceo electron-accepting units and zinc porphyrin (ZnP) or ferrocene (Fc) electron-donating moieties, respectively. Both, the donor and acceptor are covalently connected by oFL bridges of variable length. 

Cornelia van der Pol, Martin R. Bryce, Mateusz Wielopolski, Carmen Atienza-Castellanos, Dirk M. Guldi, Salvatore Filippone, Nazario Martin. Energy Transfer in Oligofluorene-Cgo and Cgo-Oligofluorene-Cgo Donor-Acceptor Conjugates. J. Org. Chem. 2007, 72, 6662. 

In an interesting development the Philp group investigated the effect of competition in a library comprising four molecules [42], Two of the molecules contain donor groups which can bond with the two other molecules that have acceptor groups. There is the potential therefore to form donor-acceptor conjugates that template the formation of similar molecules, in the manner discussed above, that is, A + B + T A B T followed by covalent bond formation (A B T T T)... 

Pinzon, J.R., Plonska-Brzezinska, M.E., Cardona, C.M. et al. (2008) ScsNOCgo-ferrocene electron-donor/acceptor conjugates as promising materials for photovoltaic applications. Angewandte Chemie International Edition, 47, 4173 176. 

Kogej, T., Beljonne, D., Meyers, F., Perry, J.W., Marder, S.R., Bredas, J.L. Mechanism for enhancement of two-photon absorphon in donor-acceptor conjugated chromophores. Chem. Phys. Lett. 298, 1-6 (1998)... 

In this section we present two studies on energy properties of solvated systems. In the first we shall analyze the solvent effects on the stability of isomers of glycine and alanine in water solution, whereas in the second we sheill analyze the solvent induced changes on the structures of donor-acceptor conjugated systems. The two studies represent two examples of application of solvation continuum models in two different important fields... 

Alternating carbazole-quinoline 99 and phenothiazine-quinoline donor-acceptor conjugated copolymers and a corresponding oligomer were synthesized by Jenekhe et al. and their solution and sohd-state photophysics were investigated (Scheme 26) (01MM7315). 

Control over the electron transfer process has been achieved by binding tetra-thiafulvalene derivatives to shortened SWCNTs through their esterification, using spacers with different length [132]. In this way, a fine-tuned donor acceptor conjugate was produced with successful control over the recombination process, as a functirai of the dmior-acceptor separation. 

Wu, J.S., Cheng, S.W., Cheng, Y.J., Hsu, C.S., 2015. Donor-acceptor conjugated polymers based on multifused ladder-type arenes for organic solar cells. Chem. Soc. Rev. 44,1113-1154. 

D. Udaya, A. John, G., M. V, A. Donor-Acceptor Conjugated Polymers and Their Nanocomposites for Photonic Applications. In Nonlinear Optics N. Kamanina, Ed. InTech, 2012. 

H.-J. Yen, H. Tsai, C.-Y. Kuo, W. Nie, A. D. Mohite, G. Gupta, J. Wang, J.-H. Wu, G.-S. Liou, H.-L. Wang, Flexible Memory Devices with Tunable Electrical Bistability via Controlled Energetics in Donor-Donor and Donor-Acceptor Conjugated Polymers. /. Mater. Chem. C 2014,2,4374. 

P.-T. Wu, T. Bull, E S. Kim, C. K. Luscombe, S. A. Jenekhe, Organometallic Donor-Acceptor Conjugated Polymer Semiconductors Tunable Optical, Electrochemical, Charge Transport, and Photovoltaic Properties. Macromolecules 2009,42, 671-681. 

M. G. Murali, U. Dalimba, K. Sridharan, Synthesis, Characterization, and Nonlinear Optical Properties of Donor-acceptor Conjugated Polymers and Polymer/Ag Nanocomposites. /. Mater. Sci. 2012,47, 8022-8034. 

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