Molecular electronics applications

R. S. Phadke, Immobilization of enzymes/coenzymes for molecular electronics applications, BioSystems, 35, 179-182 (1995). 

Due to the large number of metals that can form TNT EMFs and the usually wide cage-size distribution obtained in each case, the number of different compounds that have been described and studied by electrochemistry is quite large. All of these new fascinating compounds usually show very rich redox properties and therefore have been considered promising candidates for molecular electronic applications, such as photovoltaics. The redox behavior of these compounds is influenced by the size and symmetry of the carbon cage and the nature of the metal. 

This chapter describes different synthetic approaches towards the fabrication of candidate molecules for use in molecular electronics applications with an emphasis on thiol end-capped jr-conjugated molecules, followed by a survey of the electronic transmission properties in two- and three-terminal devices. 

Molecular electronic applications are also covered in the contribution from Zhou and Hagelberg discussing interactions of various organic molecules with silicon surface, whereas Zhou et al. concentrate on fullerene deposition on silicon and GaAs surfaces. 

Single-walled carbon nanotubes, SWNT, having a diameter of 0.7 nm were electro-chemically derivatized on the sides and ends with diazonium tetrafluoroborate derivatives. In this process the estimated degree of functionality was about 1 out of every 20 to 30 carbons in the nanotube. These chemically modified nanotubes have applications in polymer composite materials, molecular electronic applications, and sensor devices. 

Molecular electronics applications will, however, require decoupling the electronic structure of the polymer architecture from the supporting substrate. Moreover, extending the material base from metals to the comparatively heterogeneous group of bulk insulators offers the potential for tailoring the substrate properties to the specific, application-oriented needs. 

J. Leroy, J. Levin, S. Sergeyev and Y. Geerts, Practical one-step synthesis of symmetrical Uquid crystalline dialkyloUgothiophenes for molecular electronic applications, Chem. Lett., 35, 166-167 (2006). 

This method has gained importance in recent time in view of the importance of linear acenes in molecular electronics applications. The following synthesis of substituted heptacene demonstrates the utility of this methodology (Scheme 16.28) [31]. 

Metallophthalocyanine polymers offer good stability in thermal, chemical, hydrolytic and photochemical environments. The reversible redox property and cycle stability of phthalocyanine compounds and their polymers make them useful as active components in sensors, switches, diodes, memory devices, NLO materials, etc. different types of phthalocyanine polymers are available and they are amenable to chemical modifications to suit the devices requirements. It is possible to exercise chemical control of the properties of the phthalocyanine polymers as well as functionalize other conducting polymers with the characteristics of phthalocyanines. Hence phthalocyanine polymers have become potential candidates for producing useful and viable materials for electronic, optoelectronic and molecular electronic applications. 

Berry describes transition metal compounds in which there are chains of metal atoms. Such compounds are often considered as potential molecular wires for molecular electronic applications and the conductance of these compounds at the molecular level is discussed. In addition to compounds that feature homometallic chains, those with heterometallic chains are also described. 

Birge, R. (1990) Photophysics and molecular electronic applications of the rhodopsins. Annu. Rev. Phys. Chem.,... 

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