Bifunctional organic molecules

An analogous investigation was made [27] with donor-acceptor pairs such as those depicted in Fig. 7. The donor-acceptor pairs I-V presented in this figure are separated by various numbers, n, of similar chemical bonds, a so-called n-bond system. The more electron-attracting group is the dicyanovinyl group. In ref. 27, the n-bond systems were investigated for n = 4, 6, 8, 10, 12. Pulse radiolysis experiments under conditions similar to 

Studies of fluorescence quenching in 8-bond pairs in solvents such as diethylether and acetonitrile, allowed a rate of the photoinduced intramolecular electron transfer of the order of 109s 1 to be estimated, showing that very rapid intramolecular transfer can also occur in the excited bifunctional molecule. 

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On detailed electrical characteristics of a SET transistor utilizing charging effects on metal nanoclusters were reported by Sato et al. [26]. A self-assembled chain of colloidal gold nanoparticles was connected to metal electrodes, which were formed by electron-beam lithography. The cross-linking of the particles as well as their connection to the electrodes results from a linkage by bifunctional organic molecules, which present the tunnel barriers. 

Hossain, M. Z., Yamashita, Y., Mukai, K. and Yoshinobu, J. Selective functionalization of the Si(100) surface by switching the adsorption linkage of a bifunctional organic molecule. Chemical Physics Letters 388, 27 (2004). 

Very many coordination compounds are known between metal atoms and bifunctional organic molecules, where the binding is partly normal covalent links and partly coordinate links for example, copper acetate solution mixed with acetylacetone gives a blue compound that is non-ionized and can be vaporized unchanged. It can be formulated ... 

Using bifunctional organic molecules (e.g., 1,3-butadiene) and hydrosilanes, the silicon bridging units in the polymer can be varied (Scheme 15). Because of their low ceramic yield and the low thermal stability, polycarbosilanes containing longer hydrocarbon bridges are not suitable for preceramic... 

Bifunctional spacer molecules of different sizes have been used to construct nanoparticle networks formed via self-assembly of arrays of metal colloid particles prepared via reductive stabilization [88,309,310]. A combination of physical methods such as TEM, XAS, ASAXS, metastable impact electron spectroscopy (MIES), and ultraviolet photoelectron spectroscopy (UPS) has revealed that the particles are interlinked through rigid spacer molecules with proton-active functional groups to bind at the active aluminium-carbon sites in the metal-organic protecting shells [88]. 

To understand the structural requirements for a molecule to promote cytochrome c electrochemistry at gold electrodes, over 50 bifunctional organic compounds (X Y, where X is a surface-active functional group, Y is the protein-interactive ftmctionality, and is the linking structure) were investigated (21) to assess their ability to promote cytochrome c electrochemistry at a gold electrode. The results can be summarized as follows ... 

The mechanism of the catalytic action of metal adlayers in the oxidation of organic molecules has been interpreted by using several models including a third-body effect, an electronic effect, and the bifunctional catalyst mechanism. 

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