Molecular optoelectronic materials

As noted at above, organic semiconductors can be divided into two major classes of materials, small molecules and polymers. This section reviews some of the more common small molecules currently used in organic electronics. The following section considers the polymers. 

Molecular organic semiconductors are generally deposited by vacuum evaporation as they are typically insoluble and thus difficult to spin-cast or ink-jet print, but are stable and have reasonable vapor pressures and are therefore evaporable. Vacuum evaporation is more complex than spin-casting but provides quite pure materials with well-controlled structure and layer thickness. It is also straightforward to produce multilayer stmctures by evaporation. 

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Hampsch, H. L. Yang, J. Wong G. K Torkelson, J. M. Macromolecules 1990,23, 3648. Lackritz, H. S. Torkelson, J. M. "Polymer Physics of Poled Polymers for Second Order Nonlindear Optics" Chapter 8 in Molecular Optoelectronics Materials, Physics, and Devices, Zyss, J., Ed. Academic Press New York, 1993, in press. 

Also fascinating developments in various fields of applications such as optoelectronic-, materials- and medical applications are just barely touched. Our main intention was to put the focus on molecular fullerene chemistry. 

Khanarian, G., Ed. Molecular and Polymeric Optoelectronic Materials Fundamentals and Applications SPIE San Diego, 1986 Vol. 682. 

The area of molecular nonlinear optics has been rejuvenated by efforts to investigate three-dimensional multipolar systems, functionalized polymers as optoelectronic materials, near infrared optical parametric oscillators and related aspects.71 There have been some advances in chromophore design for second-order nonlinear optical materials 72 these include onedimensional CT molecules, octopolar compounds and organometallics. Some of the polydiacetylenes and poly(/>-phenylenevinylene)s appear to possess the required properties for use as third-order nonlinear optical materials for photonic switching.73... 

Photochromic processes are often observed both in solution and in the solid state, thus making for facile incorporation of photochromies in films, in membranes, and as dopants in host matrices—prerequisites for the construction of molecular optoelectronic devices. Section 2.3.1 focuses on the materials and supramolecular systems prepared from photochromic systems. For more comprehensive descriptions of the basic photochemical processes the reader is referred to any of the numerous reviews on the subject [47, 51, 89, 159-162]. 

Intermolecular hydrosilylation of diethynylsilanes with dihydro-substituted silicon compounds gives high molecular weight polymers -SiR2CH=CH- (e. g., [30]). The polymeric products obtained in the above-mentioned reactions are suitable substrates for ceramic and optoelectronic materials. 

Curran SA, Ajayan PM, Blau WJ, Carroll DL, Coleman JN, Dalton AB, Davey AP, Drury A, McCarthy B, Maier S, Strevens A (1998) A composite from poly(m-phenylenevinylene-co-2,5-dioctoxy-p-phenylenevinylene) and carbon nanotubes a novel material for molecular optoelectronics. Adv Mater 10 1091... 

Even though the spiro concept has been used mainly to improve the morphological stability of low-molecular-weight materials for optoelectronic applications, it has also proven its benefits in the development of polymeric materials. 

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