Transfer agents, charge

The structure-property relations of fullerenes, fullerene-derived solids, and carbon nanotubes are reviewed in the context of advanced technologies for carbon-hased materials. The synthesis, structure and electronic properties of fullerene solids are then considered, and modifications to their structure and properties through doping with various charge transfer agents are reviewed. Brief comments are included on potential applications of this unique family of new materials. 

Charge-transfer agent used to generate, by oxidation or reduction, positive or negative charges in an intrinsically conducting polymer. 

Note 1 The bulk electrical conductivity of an intrinsically conducting polymer is comparable to that of some metals and results from its macromolecules acquiring positive or negative charges through oxidation or reduction by an electron acceptor or donor (charge-transfer agent), termed a dopant. 

When naphthalene is used as a charge transfer agent, near quantitative yields of the M2E and M2E2 derivatives can be obtained , This synthetic procedure also eliminates the problems associated with formation of side products. Either reflux or sonication can be used with equal facility in reaction (f). 

Organic polymers that possess the electronic, magnetic, and optical properties of metals are known as conductive polymers (CPs). Because of their conjugated u electron backbones, they can be oxidized or reduced more easily and more reversibly than conventional polymers with charge-transfer agents, also commonly called dopants, a term borrowed from condensed matter physics. While retaining some of the mechanical properties of polymers, they do not melt or dissolve in common organic solvents, a major impediment to their widespread commercialization in the same manner as traditional plastics. The same electronic structure that confers electrical conductivity to these polymers also contributes to their intractability and instability. 

An alternative way is to divide the overall process of water splitting into two stages, each being conducted in a separate photoelectrochemical cell. Both cells are coupled with the aid of a certain intermediate substance, which acts as a charge transfer agent and is not consumed in the course of the overall process, but only provides the connection in series of the chemical potentials developed in both cells. Apparently, such a scheme imitates the combination of two photosystems in photosynthesis occurring in green plants. 

Thus, a compound like tetracyanobenzoquinone will be a better charge transfer agent than quinone. 

The simplest and most direct method of converting monomer to polymer is known as bulk or mass polymerization. A typical charge might consist of monomer, a monomer-soluble initiator, and perhaps a charge-transfer agent. Simple rate and heat transfer problems due to reaction kinetics generally create problems with bulk polymerization. However, some polymers such as polystyrene are sometimes made in bulk. 

A very wide variety of charge transfer agents has been used for the study of bases, particularly ir-bases. Fortunately, a complete coverage of this subject is available in Briegleb s recent book (41). We shall tabulate charge transfer data only for a few acids such as iodine which have been used for investigation of a wide variety of base types. 

The dopants (e.g., dyes like rose bengal, methyl violet, methylane blue, etc.) re charge-transfer agents. The dyes have the ability to absorb fight and sensitize the polymer by the addition of electron transfer. The technique of chemical modification improves the speclral response, giving a higher speed of... 

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