Electron self assembled systems

Mechanically interlocked molecular compounds, including catenanes, rotax-anes, and carceplex, are constituted of molecules composed of two or more components that cannot be separated from each other [95-98]. The development of strategy for achieving controlled self-assembling systems by non-covalent interaction enables one to prepare such attractive compounds for applications in nanoscale molecular devices. The dithiafulvene derivatives are effective electron donors, which are good candidates to form those supramolecular systems with appropriate acceptors by virtue of intermolec-ular CT interactions. In this chapter, dithiafulvene polymers forming rotax-ane structures are especially described. 

There have been several attempts to produce highly efficient artificial electron transport membranes modeled after the electron transfer processes in the sequence of oxidation/reduction reactions of photosynthesis in the chlorophyll pigments. Various self-assembly systems have been investigated, such as, for example, liquid membranes, bilayer membranes, micelles, LB-films (named after Langmuir and Blodgett). 

The covalently linked or self-assembled systems constructed from free-base porphyrins or metalloposphyrins and various quenchers and related studies of excited-state energy-transfer and electron-transfer processes in such systems are a widely studied topic of contemporary supramolecular chemistry. There are two major reasons for the exceptional interest in the topic a challenge to synthesize artificial systems for harvesting solar energy of... 

The use of peptide-derived lipids (Glu-1, Phe-1, and Phe-2) as organic stationary phases also has been described in this entry. These lipids not only have high potential ability as a self-assembling system but also are attractive as a carbonyl Tr-electron source. As a result, double-alkylated L-glutamide-derived stationary phase has been developed and extremely high selectivity is detected in HPLC as predicted. Polymeric types of peptide-derived hpids were also considered and developed, but their selectivity could not exceed that of the monomeric type hpids. This is probably due to the fact that radical polymerization of peptide-derived monomers disturb the stereoregularity of the resultant polymer main chain, and thus, sufficient molecular ordering is not obtained to increase the selectivity (multiple TT-TT interaction). Finally, it is concluded that subsidiary weak interactions, such as tt-tt interaction, can... 

Pelesko, John A. Self Assembly The Science of Things That Put Themselves Together. Boca Raton, Ela. Chapman and Hall/CRG, 2007. Discusses natural self-assembling systems such as crystals and soap films and goes on to discuss viruses and self-assembly of DNA cubes and electronic circuits. Excellent introduction to a field of growing importance. 

A significant research effort has been devoted to the design and application of various supramolecular self-assembled systems in photoelectrochemical solar cells. Fullerenes, fullerene derivatives, and carbon nanotubes are typically used as electron acceptor components of such systems. Porphyrins, phthalocyanines, ruthenium complexes, conjugated oligomers, and polymers are applied as electron donor counterparts. 

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