Optical properties of conjugated polymers

Main structural and optical properties of conjugated polymers... 

R Kiebooms, R Menon, and K Lee, Synthesis, electrical, and optical properties of conjugated polymers, in Handbook of Advanced Electronic and Photonic Materials and Devices, FLS. Nalwa, Ed., Academic Press, New York, 2001, pp. 1-102. 

The optical properties of conjugated polymers primarily arise from the 7t-bonds in the polymer backbone. Alignment of 7i-bonds leads to electron delocalization, also referred to as conjugation or -conjugation. Theoretically, backbone 7i-electrons can be delocalized along the entire length of the polymer if the 7i-bonds are all aligned however, twists in the backbone and defects in the polymer structure at... 

S. Abe, Excitonic Effects in the Linear and Nonlinear Optical Properties of Conjugated Polymers, in N. S. Sariciftci (Ed.), Primary Photoexcitations in Conjugated Polymers, World Scientific, Singapore, 1997, p. 115. 

On the basis of the measurements of the optical properties of conjugated polymers described in this section it is possible to construct energy level diagrams for the lowest lying electronic excitations. Some examples of the results obtained are illustrated in Fig. 9.25. The diagram for MeL-PPP is for data obtained with samples of the same morphology those for the other polymers combine data for samples of different morphology and for related polymers, and are indicative rather than exact. 

Kijima, M. Kinoshita, L Hiroki, K. Shirakawa, H. Yoshikawa, K. Mishima, Y. Sasaki, N. Optical properties of conjugated polymers having linear carbon moieties. Curr. Appl. Phys. 2002, 2, 289-294. 

The optical properties of conjugated polymers are a direct consequence of the electronic structure, which is determined both by the chemical and the geometrical structure of the polymer. As the thermochromic transition is reversible, we do not expect to find covalent bonds formed, or destroyed, in the thermochromic transition. It is rather the geometry that is the candidate for changing the electronic structure of the polymer in a reversible manner. 

J.A. Dearo, K.D. Weston, S.K. Buratto, and U. Lemmer, Mesoscale optical properties of conjugated polymers probed by near-field scanning optical microscopy. Chem. Phys. Lett., 277, 532 (1997). 

B. Kirtman, Nonlinear Optical Properties of Conjugated Polymers from Ab Initio Finite Oligomer Calculations. Int. J. Quantum Chem. 1992,43,147-158. 

Impact of Charge Injection on the Optical Properties of Conjugated Polymers... 

Finally, optical properties of conjugated polymers are currently poorly described. This is due to the fact that the local functionals currently in use (LDA and GGAs) fail to capture subtle charge displacements at the ends of a long molecular chain. Recently, a solution to this important problem, using the sophisticated ultra nonlocal Vignale-Kohn xc functional, has come much closer. ... 

This book was written with two kinds of readers in mind. One kind of readers are experimentalists who wish to understand and interpret their experimental data in terms of the fundamental electronic and optical properties of conjugated polymers. The other type of readers are theoretical and computational chemists and physicists who both want to understand the fundamental properties of conjugated polymers, as well as wishing to develop models and perform calculations of their own. For these readers there are a number of appendices containing material too technical for the main chapters. In particular, Appendix H gives a brief review of the DMRG method. 

Kirtman, B. 1992. Nonlinear optical properties of conjugated polymers from ab initio finite oligomer calculations. International Journal of Quantum Chemistry 43 (1) 147. 

Bubek, C., Relationship between structure and third-order nonlinear optical properties of conjugated polymers. Nonlinear Opt., 10, 13-22 (1995). 

A simple model describes the linear and nonlinear optical properties of conjugated polymers [e.g., oligo(thiophene)s] found from the measurements of the optical band gap of two oligomers of different length, without the need for supercomputing power [409]. Photocatalytic CO2 fixation is observed in photoirradiation experiments on a PAT film immersed in ethanol solution containing 4-butylphenol in a CO2 atmosphere [367,368]. An electric field induces changes in the optical properties of PATs and poly(thienylene vinylenejs. The induced absorption is proportional to the square of the applied electric field and its line shape is field invariant [410]. 

SYNTHESIS, ELECTRICAL, AND OPTICAL PROPERTIES OF CONJUGATED POLYMERS... 

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