Insulated Molecular Wires

Figure 58 A shish-kebab porphyrin [708-710] proposed for a molecular wire insulated by the porphyrin rings [707].

Many other opportunities exist due to the enormous flexibility of the preparative method, and the ability to incorporate many different species. Very recently, a great deal of work has been published concerning methods of producing these materials with specific physical forms, such as spheres, discs and fibres. Such possibilities will pave the way to new application areas such as molecular wires, where the silica fibre acts as an insulator, and the inside of the pore is filled with a metal or indeed a conducting polymer, such that nanoscale wires and electronic devices can be fabricated. Initial work on the production of highly porous electrodes has already been successfully carried out, and the extension to uni-directional bundles of wires will no doubt soon follow. 

F. Cacialli, J.S. Wilson, J.J. Michels, C. Daniel, C. Silva, R.H. Friend, N. Severin, P. Samori, J.P. Rabe, M.J. O Connell, P.N. Taylor, and H.L. Anderson, Cyclodextrin-threaded conjugated polyrotaxanes, as insulated molecular wires with reduced interstrand interaction, Nat. Mater., 1 160-164, 2002. 

Frampton Ml, Anderson HL (2007) Insulated molecular wires. Angew Chem Int Ed 46 1028-1064... 

DNA - a Molecular Wire or an Insulator - The rate, as well as the extent, of electron and hole migration within DNA had been a topic of intense experimental and theoretical interest and dispute.60 ESR studies have made significant contributions to the understanding of these important phenomenon. 

Debieu D, Deschavanne PJ, Midander J, Larsson A, Malaise EP (1985) Survival curves of glutathione synthetase deficient human fibroblasts correlation between radiosensitivity in hypoxia and glutathione synthetase activity. Int J Radiat Biol 48 525-543 Debije MG, Milano MT, Bernhard WA (1999) DNA responds to ionizing radiation as an insulator not as a molecular wire". Angew Chem Int Ed Engl 38 2752-2756 Debije MG, Razskazovskiy Y, Bernhard AW (2001) The yield of strand breaks resulting from direct-type effects in crystalline DNA X-irradiated at 4 K and room temperature. J Am Chem Soc 123 2917-2918... 

Figure 11.30 An insulated molecular wire based on a platinum(II) polyalkyne surrounded by two long-chain diphosphines. The polyalkyne wire (shown dark in the middle of the structure) is barely visible within the insulation.45...

Figure 4.6 shows the schematic diagrams of ciclodextrins, polyaniline with emeraldine base, and inclusion complex formation of cyclodextrins and a conducting polymer chain insulated molecular wire. 

In some cases, taking the opposite approach, using slower solvating, higher molecular weight and less efficient phthalates, such as DINP and DIDP, has been shown to increase plant output in certain calendering and extrusion operations. Table II compares results of a wire insulation extrusion study with DOP vs. DINP. 

L. A., Hall, M.J., Alpin, R.T. and Anserson, H.L. (2000) Insulated molecular wires Synthesis of conjugated polyrotaxanes by Suzuki coupling in water. Angewandte Chemie (International Ed. in English), 39, 3456-60. 

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