Conjugated polymers photophysics

Huser T, Yan M, Rothberg LJ (2000) Single chain spectroscopy of conformational dependence of conjugated polymer photophysics. Proc Natl Acad Sci 97 11187-11191... 

The chapter is organized as follows the second section will discuss the photophysics of conjugated polymer/fullerene composites as a standard model for a charge-generating layer in plastic solar cells. Pristine polymer devices will be discussed in the third section while bilayer and interpenetrating network devices are presented in Sections 4 and 5. Section 6 contains some remarks on large area plastic solar cells and Section 7 conclusions. 

The role of disorder in the photophysics of conjugated polymers has been extensively described by the work carried out in Marburg by H. Bassler and coworkers. Based on ultrafast photoluminescence (PL) (15], field-induced luminescence quenching [16J and site-selective PL excitation [17], a model for excited state thermalizalion was proposed, which considers interchain exciton migration within the inhomogenously broadened density of states. We will base part of the interpretation of our results in m-LPPP on this model, which will be discussed in some detail in Sections 8.4 and 8.6. 

Because of the great importance of PF as a class of conjugated polymers with excellent optical and electronic properties, several theoretical studies were performed to better understand the electronic structure and the photophysical processes, which occur in these materials [260-265],... 

L. Ding, D.A.M. Egbe, and F.E. Karasz, Photophysical and optoelectronic properties of green-emitting alkoxy-substituted PE/PV hybrid conjugated polymers, Macromolecules, 37 6124-6131,2004. 

Y. Zhu, M.M. Alam, and S.A. Jenekhe, Regioregular head-to-tail poly(4-alkylquinoline)s synthesis, characterization, self-organization, photophysics, and electroluminescence of new n-type conjugated polymers, Macromolecules, 36 8958-8968, 2003. 

McQuade DT, Kim J, Swager TM (2000) Two-dimensional conjugated polymer assemblies interchain spacing for control of photophysics. J Am Chem Soc 122 5885-5886... 

Abstract Conjugated polymers have many unique photophysical properties that make them useful for a variety of applications within the fields of chemistry, molecular biology, and medicine, specifically their ability to produce a conformation-dependant spectral signature reflective of changes in their local environment. This physical property makes conjugated polymers an indispensible tool in the toolbox of fluorescent reporters, and within this chapter, their utilization as molecular probes for studying protein structure and conformation is emphasized. 

Ley KD, Schanze KS Coord Chem Rev (1998) 171 287-307 Photophysics of metal-organic n-conjugated polymers... 

As expected, the coordination of Pt markedly influences the photophysical characteristics of the PPE. The photoluminescence is efficiently quenched, and the absorption maximum in the visible regime experiences a hypsochromic shift. The charge-carrier mobility of different EHO-OPPE-Pt samples was determined by TOE measurements as described above for the neat EHO-OPPE. The shape of the photocurrent transients of all EHO-OPPE-Pt samples was similar to those shown in Figs. 6 and 7 for the neat EHO-OPPE. This indicates that these organometallic conjugated polymers networks are also characterized... 

Applications of conjugated polymers-NCs hybrids in various (opto-)electronic devices and sensors require a deeper understanding of the relationship between their chemical and photophysical properties and their structure at different levels from the molecular to the bulk material. This requires the use of complementary methods... 

In conjugated polymers and oligomers, the behavior of photoexcited states obeys general rules of molecular photophysics, such as the Kasha [88] and Vavilov [77] rules. These are empirical observations, rather than exact statements or laws. However, they provide a useful basis for discussion. The Kasha rule states that fluorescence occurs from the lower-lying excited state, independently of the excitation energy. The Vavilov rule states that the fluo-... 

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